<?php
/**
 * PHPExcel
 *
 * Copyright (c) 2006 - 2011 PHPExcel
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * @category   PHPExcel
 * @package    PHPExcel_Calculation
 * @copyright  Copyright (c) 2006 - 2011 PHPExcel (http://www.codeplex.com/PHPExcel)
 * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
 * @version    1.7.6, 2011-02-27
 */


/** PHPExcel root directory */
if (!defined('PHPEXCEL_ROOT')) {
    /**
     * @ignore
     */
    define('PHPEXCEL_ROOT', dirname(__FILE__) . '/../');
    require(PHPEXCEL_ROOT . 'PHPExcel/Autoloader.php');
}


if (!defined('CALCULATION_REGEXP_CELLREF')) {
    //    Test for support of \P (multibyte options) in PCRE
    if(defined('PREG_BAD_UTF8_ERROR')) {
        //    Cell reference (cell or range of cells, with or without a sheet reference)
        define('CALCULATION_REGEXP_CELLREF','((([^\s,!&%^\/\*\+<>=-]*)|(\'[^\']*\')|(\"[^\"]*\"))!)?\$?([a-z]{1,3})\$?(\d{1,7})');
        //    Named Range of cells
        define('CALCULATION_REGEXP_NAMEDRANGE','((([^\s,!&%^\/\*\+<>=-]*)|(\'[^\']*\')|(\"[^\"]*\"))!)?([_A-Z][_A-Z0-9\.]*)');
    } else {
        //    Cell reference (cell or range of cells, with or without a sheet reference)
        define('CALCULATION_REGEXP_CELLREF','(((\w*)|(\'[^\']*\')|(\"[^\"]*\"))!)?\$?([a-z]{1,3})\$?(\d+)');
        //    Named Range of cells
        define('CALCULATION_REGEXP_NAMEDRANGE','(((\w*)|(\'.*\')|(\".*\"))!)?([_A-Z][_A-Z0-9\.]*)');
    }
}


/**
 * PHPExcel_Calculation (Singleton)
 *
 * @category    PHPExcel
 * @package        PHPExcel_Calculation
 * @copyright    Copyright (c) 2006 - 2011 PHPExcel (http://www.codeplex.com/PHPExcel)
 */
class PHPExcel_Calculation {

    /**    Constants                */
    /**    Regular Expressions        */
    //    Numeric operand
    const CALCULATION_REGEXP_NUMBER        = '[-+]?\d*\.?\d+(e[-+]?\d+)?';
    //    String operand
    const CALCULATION_REGEXP_STRING        = '"(?:[^"]|"")*"';
    //    Opening bracket
    const CALCULATION_REGEXP_OPENBRACE    = '\(';
    //    Function (allow for the old @ symbol that could be used to prefix a function, but we'll ignore it)
    const CALCULATION_REGEXP_FUNCTION    = '@?([A-Z][A-Z0-9\.]*)[\s]*\(';
    //    Cell reference (cell or range of cells, with or without a sheet reference)
    const CALCULATION_REGEXP_CELLREF    = CALCULATION_REGEXP_CELLREF;
    //    Named Range of cells
    const CALCULATION_REGEXP_NAMEDRANGE    = CALCULATION_REGEXP_NAMEDRANGE;
    //    Error
    const CALCULATION_REGEXP_ERROR        = '\#[A-Z][A-Z0_\/]*[!\?]?';


    /**    constants */
    const RETURN_ARRAY_AS_ERROR = 'error';
    const RETURN_ARRAY_AS_VALUE = 'value';
    const RETURN_ARRAY_AS_ARRAY = 'array';

    private static $returnArrayAsType    = self::RETURN_ARRAY_AS_VALUE;


    /**
     *    Instance of this class
     *
     *    @access    private
     *    @var PHPExcel_Calculation
     */
    private static $_instance;


    /**
     *    Calculation cache
     *
     *    @access    private
     *    @var array
     */
    private static $_calculationCache = array ();


    /**
     *    Calculation cache enabled
     *
     *    @access    private
     *    @var boolean
     */
    private static $_calculationCacheEnabled = true;


    /**
     *    Calculation cache expiration time
     *
     *    @access    private
     *    @var float
     */
    private static $_calculationCacheExpirationTime = 15;


    /**
     *    List of operators that can be used within formulae
     *    The true/false value indicates whether it is a binary operator or a unary operator
     *
     *    @access    private
     *    @var array
     */
    private static $_operators            = array('+' => true,    '-' => true,    '*' => true,    '/' => true,
                                                '^' => true,    '&' => true,    '%' => false,    '~' => false,
                                                '>' => true,    '<' => true,    '=' => true,    '>=' => true,
                                                '<=' => true,    '<>' => true,    '|' => true,    ':' => true
                                               );


    /**
     *    List of binary operators (those that expect two operands)
     *
     *    @access    private
     *    @var array
     */
    private static $_binaryOperators    = array('+' => true,    '-' => true,    '*' => true,    '/' => true,
                                                '^' => true,    '&' => true,    '>' => true,    '<' => true,
                                                '=' => true,    '>=' => true,    '<=' => true,    '<>' => true,
                                                '|' => true,    ':' => true
                                               );

    /**
     *    Flag to determine how formula errors should be handled
     *        If true, then a user error will be triggered
     *        If false, then an exception will be thrown
     *
     *    @access    public
     *    @var boolean
     *
     */
    public $suppressFormulaErrors = false;

    /**
     *    Error message for any error that was raised/thrown by the calculation engine
     *
     *    @access    public
     *    @var string
     *
     */
    public $formulaError = null;

    /**
     *    Flag to determine whether a debug log should be generated by the calculation engine
     *        If true, then a debug log will be generated
     *        If false, then a debug log will not be generated
     *
     *    @access    public
     *    @var boolean
     *
     */
    public $writeDebugLog = false;

    /**
     *    Flag to determine whether a debug log should be echoed by the calculation engine
     *        If true, then a debug log will be echoed
     *        If false, then a debug log will not be echoed
     *    A debug log can only be echoed if it is generated
     *
     *    @access    public
     *    @var boolean
     *
     */
    public $echoDebugLog = false;


    /**
     *    An array of the nested cell references accessed by the calculation engine, used for the debug log
     *
     *    @access    private
     *    @var array of string
     *
     */
    private $debugLogStack = array();

    /**
     *    The debug log generated by the calculation engine
     *
     *    @access    public
     *    @var array of string
     *
     */
    public $debugLog = array();
    private $_cyclicFormulaCount = 0;
    private $_cyclicFormulaCell = '';
    public $cyclicFormulaCount = 0;


    private $_savedPrecision    = 12;


    private static $_localeLanguage = 'en_us';                    //    US English    (default locale)
    private static $_validLocaleLanguages = array(    'en'        //    English        (default language)
                                                 );
    private static $_localeArgumentSeparator = ',';
    private static $_localeFunctions = array();
    public static $_localeBoolean = array(    'TRUE'    => 'TRUE',
                                            'FALSE'    => 'FALSE',
                                            'NULL'    => 'NULL'
                                          );


    //    Constant conversion from text name/value to actual (datatyped) value
    private static $_ExcelConstants = array('TRUE'    => true,
                                            'FALSE'    => false,
                                            'NULL'    => null
                                           );

    //    PHPExcel functions
    private static $_PHPExcelFunctions = array(    // PHPExcel functions
                'ABS'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'abs',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ACCRINT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::ACCRINT',
                                                 'argumentCount'    =>    '4-7'
                                                ),
                'ACCRINTM'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::ACCRINTM',
                                                 'argumentCount'    =>    '3-5'
                                                ),
                'ACOS'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'acos',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ACOSH'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'acosh',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ADDRESS'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::CELL_ADDRESS',
                                                 'argumentCount'    =>    '2-5'
                                                ),
                'AMORDEGRC'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::AMORDEGRC',
                                                 'argumentCount'    =>    '6,7'
                                                ),
                'AMORLINC'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::AMORLINC',
                                                 'argumentCount'    =>    '6,7'
                                                ),
                'AND'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOGICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Logical::LOGICAL_AND',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'AREAS'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ASC'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ASIN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'asin',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ASINH'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'asinh',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ATAN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'atan',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ATAN2'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::ATAN2',
                                                 'argumentCount'    =>    '2'
                                                ),
                'ATANH'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'atanh',
                                                 'argumentCount'    =>    '1'
                                                ),
                'AVEDEV'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::AVEDEV',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'AVERAGE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::AVERAGE',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'AVERAGEA'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::AVERAGEA',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'AVERAGEIF'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::AVERAGEIF',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'AVERAGEIFS'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '3+'
                                                ),
                'BAHTTEXT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '1'
                                                ),
                'BESSELI'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::BESSELI',
                                                 'argumentCount'    =>    '2'
                                                ),
                'BESSELJ'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::BESSELJ',
                                                 'argumentCount'    =>    '2'
                                                ),
                'BESSELK'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::BESSELK',
                                                 'argumentCount'    =>    '2'
                                                ),
                'BESSELY'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::BESSELY',
                                                 'argumentCount'    =>    '2'
                                                ),
                'BETADIST'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::BETADIST',
                                                 'argumentCount'    =>    '3-5'
                                                ),
                'BETAINV'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::BETAINV',
                                                 'argumentCount'    =>    '3-5'
                                                ),
                'BIN2DEC'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::BINTODEC',
                                                 'argumentCount'    =>    '1'
                                                ),
                'BIN2HEX'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::BINTOHEX',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'BIN2OCT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::BINTOOCT',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'BINOMDIST'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::BINOMDIST',
                                                 'argumentCount'    =>    '4'
                                                ),
                'CEILING'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::CEILING',
                                                 'argumentCount'    =>    '2'
                                                ),
                'CELL'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'CHAR'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::CHARACTER',
                                                 'argumentCount'    =>    '1'
                                                ),
                'CHIDIST'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::CHIDIST',
                                                 'argumentCount'    =>    '2'
                                                ),
                'CHIINV'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::CHIINV',
                                                 'argumentCount'    =>    '2'
                                                ),
                'CHITEST'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '2'
                                                ),
                'CHOOSE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::CHOOSE',
                                                 'argumentCount'    =>    '2+'
                                                ),
                'CLEAN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::TRIMNONPRINTABLE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'CODE'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::ASCIICODE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'COLUMN'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::COLUMN',
                                                 'argumentCount'    =>    '-1',
                                                 'passByReference'    =>    array(true)
                                                ),
                'COLUMNS'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::COLUMNS',
                                                 'argumentCount'    =>    '1'
                                                ),
                'COMBIN'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::COMBIN',
                                                 'argumentCount'    =>    '2'
                                                ),
                'COMPLEX'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::COMPLEX',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'CONCATENATE'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::CONCATENATE',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'CONFIDENCE'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::CONFIDENCE',
                                                 'argumentCount'    =>    '3'
                                                ),
                'CONVERT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::CONVERTUOM',
                                                 'argumentCount'    =>    '3'
                                                ),
                'CORREL'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::CORREL',
                                                 'argumentCount'    =>    '2'
                                                ),
                'COS'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'cos',
                                                 'argumentCount'    =>    '1'
                                                ),
                'COSH'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'cosh',
                                                 'argumentCount'    =>    '1'
                                                ),
                'COUNT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::COUNT',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'COUNTA'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::COUNTA',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'COUNTBLANK'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::COUNTBLANK',
                                                 'argumentCount'    =>    '1'
                                                ),
                'COUNTIF'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::COUNTIF',
                                                 'argumentCount'    =>    '2'
                                                ),
                'COUNTIFS'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '2'
                                                ),
                'COUPDAYBS'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::COUPDAYBS',
                                                 'argumentCount'    =>    '3,4'
                                                ),
                'COUPDAYS'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::COUPDAYS',
                                                 'argumentCount'    =>    '3,4'
                                                ),
                'COUPDAYSNC'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::COUPDAYSNC',
                                                 'argumentCount'    =>    '3,4'
                                                ),
                'COUPNCD'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::COUPNCD',
                                                 'argumentCount'    =>    '3,4'
                                                ),
                'COUPNUM'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::COUPNUM',
                                                 'argumentCount'    =>    '3,4'
                                                ),
                'COUPPCD'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::COUPPCD',
                                                 'argumentCount'    =>    '3,4'
                                                ),
                'COVAR'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::COVAR',
                                                 'argumentCount'    =>    '2'
                                                ),
                'CRITBINOM'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::CRITBINOM',
                                                 'argumentCount'    =>    '3'
                                                ),
                'CUBEKPIMEMBER'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_CUBE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '?'
                                                ),
                'CUBEMEMBER'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_CUBE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '?'
                                                ),
                'CUBEMEMBERPROPERTY'    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_CUBE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '?'
                                                ),
                'CUBERANKEDMEMBER'        => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_CUBE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '?'
                                                ),
                'CUBESET'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_CUBE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '?'
                                                ),
                'CUBESETCOUNT'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_CUBE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '?'
                                                ),
                'CUBEVALUE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_CUBE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '?'
                                                ),
                'CUMIPMT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::CUMIPMT',
                                                 'argumentCount'    =>    '6'
                                                ),
                'CUMPRINC'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::CUMPRINC',
                                                 'argumentCount'    =>    '6'
                                                ),
                'DATE'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::DATE',
                                                 'argumentCount'    =>    '3'
                                                ),
                'DATEDIF'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::DATEDIF',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'DATEVALUE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::DATEVALUE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'DAVERAGE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATABASE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '3'
                                                ),
                'DAY'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::DAYOFMONTH',
                                                 'argumentCount'    =>    '1'
                                                ),
                'DAYS360'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::DAYS360',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'DB'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::DB',
                                                 'argumentCount'    =>    '4,5'
                                                ),
                'DCOUNT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATABASE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Database::DCOUNT',
                                                 'argumentCount'    =>    '3'
                                                ),
                'DCOUNTA'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATABASE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Database::DCOUNTA',
                                                 'argumentCount'    =>    '3'
                                                ),
                'DDB'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::DDB',
                                                 'argumentCount'    =>    '4,5'
                                                ),
                'DEC2BIN'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::DECTOBIN',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'DEC2HEX'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::DECTOHEX',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'DEC2OCT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::DECTOOCT',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'DEGREES'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'rad2deg',
                                                 'argumentCount'    =>    '1'
                                                ),
                'DELTA'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::DELTA',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'DEVSQ'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::DEVSQ',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'DGET'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATABASE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Database::DGET',
                                                 'argumentCount'    =>    '3'
                                                ),
                'DISC'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::DISC',
                                                 'argumentCount'    =>    '4,5'
                                                ),
                'DMAX'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATABASE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Database::DMAX',
                                                 'argumentCount'    =>    '3'
                                                ),
                'DMIN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATABASE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Database::DMIN',
                                                 'argumentCount'    =>    '3'
                                                ),
                'DOLLAR'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::DOLLAR',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'DOLLARDE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::DOLLARDE',
                                                 'argumentCount'    =>    '2'
                                                ),
                'DOLLARFR'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::DOLLARFR',
                                                 'argumentCount'    =>    '2'
                                                ),
                'DPRODUCT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATABASE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Database::DPRODUCT',
                                                 'argumentCount'    =>    '3'
                                                ),
                'DSTDEV'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATABASE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Database::DSTDEV',
                                                 'argumentCount'    =>    '3'
                                                ),
                'DSTDEVP'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATABASE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Database::DSTDEVP',
                                                 'argumentCount'    =>    '3'
                                                ),
                'DSUM'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATABASE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Database::DSUM',
                                                 'argumentCount'    =>    '3'
                                                ),
                'DURATION'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '5,6'
                                                ),
                'DVAR'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATABASE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Database::DVAR',
                                                 'argumentCount'    =>    '3'
                                                ),
                'DVARP'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATABASE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Database::DVARP',
                                                 'argumentCount'    =>    '3'
                                                ),
                'EDATE'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::EDATE',
                                                 'argumentCount'    =>    '2'
                                                ),
                'EFFECT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::EFFECT',
                                                 'argumentCount'    =>    '2'
                                                ),
                'EOMONTH'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::EOMONTH',
                                                 'argumentCount'    =>    '2'
                                                ),
                'ERF'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::ERF',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'ERFC'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::ERFC',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ERROR.TYPE'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::ERROR_TYPE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'EVEN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::EVEN',
                                                 'argumentCount'    =>    '1'
                                                ),
                'EXACT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '2'
                                                ),
                'EXP'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'exp',
                                                 'argumentCount'    =>    '1'
                                                ),
                'EXPONDIST'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::EXPONDIST',
                                                 'argumentCount'    =>    '3'
                                                ),
                'FACT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::FACT',
                                                 'argumentCount'    =>    '1'
                                                ),
                'FACTDOUBLE'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::FACTDOUBLE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'FALSE'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOGICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Logical::FALSE',
                                                 'argumentCount'    =>    '0'
                                                ),
                'FDIST'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '3'
                                                ),
                'FIND'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::SEARCHSENSITIVE',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'FINDB'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::SEARCHSENSITIVE',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'FINV'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '3'
                                                ),
                'FISHER'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::FISHER',
                                                 'argumentCount'    =>    '1'
                                                ),
                'FISHERINV'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::FISHERINV',
                                                 'argumentCount'    =>    '1'
                                                ),
                'FIXED'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::FIXEDFORMAT',
                                                 'argumentCount'    =>    '1-3'
                                                ),
                'FLOOR'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::FLOOR',
                                                 'argumentCount'    =>    '2'
                                                ),
                'FORECAST'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::FORECAST',
                                                 'argumentCount'    =>    '3'
                                                ),
                'FREQUENCY'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '2'
                                                ),
                'FTEST'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '2'
                                                ),
                'FV'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::FV',
                                                 'argumentCount'    =>    '3-5'
                                                ),
                'FVSCHEDULE'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::FVSCHEDULE',
                                                 'argumentCount'    =>    '2'
                                                ),
                'GAMMADIST'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::GAMMADIST',
                                                 'argumentCount'    =>    '4'
                                                ),
                'GAMMAINV'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::GAMMAINV',
                                                 'argumentCount'    =>    '3'
                                                ),
                'GAMMALN'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::GAMMALN',
                                                 'argumentCount'    =>    '1'
                                                ),
                'GCD'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::GCD',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'GEOMEAN'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::GEOMEAN',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'GESTEP'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::GESTEP',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'GETPIVOTDATA'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '2+'
                                                ),
                'GROWTH'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::GROWTH',
                                                 'argumentCount'    =>    '1-4'
                                                ),
                'HARMEAN'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::HARMEAN',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'HEX2BIN'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::HEXTOBIN',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'HEX2DEC'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::HEXTODEC',
                                                 'argumentCount'    =>    '1'
                                                ),
                'HEX2OCT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::HEXTOOCT',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'HLOOKUP'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '3,4'
                                                ),
                'HOUR'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::HOUROFDAY',
                                                 'argumentCount'    =>    '1'
                                                ),
                'HYPERLINK'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::HYPERLINK',
                                                 'argumentCount'    =>    '1,2',
                                                 'passCellReference'=>    true
                                                ),
                'HYPGEOMDIST'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::HYPGEOMDIST',
                                                 'argumentCount'    =>    '4'
                                                ),
                'IF'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOGICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Logical::STATEMENT_IF',
                                                 'argumentCount'    =>    '1-3'
                                                ),
                'IFERROR'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOGICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Logical::IFERROR',
                                                 'argumentCount'    =>    '2'
                                                ),
                'IMABS'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMABS',
                                                 'argumentCount'    =>    '1'
                                                ),
                'IMAGINARY'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMAGINARY',
                                                 'argumentCount'    =>    '1'
                                                ),
                'IMARGUMENT'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMARGUMENT',
                                                 'argumentCount'    =>    '1'
                                                ),
                'IMCONJUGATE'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMCONJUGATE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'IMCOS'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMCOS',
                                                 'argumentCount'    =>    '1'
                                                ),
                'IMDIV'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMDIV',
                                                 'argumentCount'    =>    '2'
                                                ),
                'IMEXP'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMEXP',
                                                 'argumentCount'    =>    '1'
                                                ),
                'IMLN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMLN',
                                                 'argumentCount'    =>    '1'
                                                ),
                'IMLOG10'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMLOG10',
                                                 'argumentCount'    =>    '1'
                                                ),
                'IMLOG2'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMLOG2',
                                                 'argumentCount'    =>    '1'
                                                ),
                'IMPOWER'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMPOWER',
                                                 'argumentCount'    =>    '2'
                                                ),
                'IMPRODUCT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMPRODUCT',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'IMREAL'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMREAL',
                                                 'argumentCount'    =>    '1'
                                                ),
                'IMSIN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMSIN',
                                                 'argumentCount'    =>    '1'
                                                ),
                'IMSQRT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMSQRT',
                                                 'argumentCount'    =>    '1'
                                                ),
                'IMSUB'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMSUB',
                                                 'argumentCount'    =>    '2'
                                                ),
                'IMSUM'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::IMSUM',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'INDEX'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::INDEX',
                                                 'argumentCount'    =>    '1-4'
                                                ),
                'INDIRECT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::INDIRECT',
                                                 'argumentCount'    =>    '1,2',
                                                 'passCellReference'=>    true
                                                ),
                'INFO'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '1'
                                                ),
                'INT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::INT',
                                                 'argumentCount'    =>    '1'
                                                ),
                'INTERCEPT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::INTERCEPT',
                                                 'argumentCount'    =>    '2'
                                                ),
                'INTRATE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::INTRATE',
                                                 'argumentCount'    =>    '4,5'
                                                ),
                'IPMT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::IPMT',
                                                 'argumentCount'    =>    '4-6'
                                                ),
                'IRR'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::IRR',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'ISBLANK'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::IS_BLANK',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ISERR'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::IS_ERR',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ISERROR'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::IS_ERROR',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ISEVEN'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::IS_EVEN',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ISLOGICAL'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::IS_LOGICAL',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ISNA'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::IS_NA',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ISNONTEXT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::IS_NONTEXT',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ISNUMBER'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::IS_NUMBER',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ISODD'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::IS_ODD',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ISPMT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::ISPMT',
                                                 'argumentCount'    =>    '4'
                                                ),
                'ISREF'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ISTEXT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::IS_TEXT',
                                                 'argumentCount'    =>    '1'
                                                ),
                'JIS'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '1'
                                                ),
                'KURT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::KURT',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'LARGE'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::LARGE',
                                                 'argumentCount'    =>    '2'
                                                ),
                'LCM'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::LCM',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'LEFT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::LEFT',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'LEFTB'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::LEFT',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'LEN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::STRINGLENGTH',
                                                 'argumentCount'    =>    '1'
                                                ),
                'LENB'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::STRINGLENGTH',
                                                 'argumentCount'    =>    '1'
                                                ),
                'LINEST'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::LINEST',
                                                 'argumentCount'    =>    '1-4'
                                                ),
                'LN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'log',
                                                 'argumentCount'    =>    '1'
                                                ),
                'LOG'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::LOG_BASE',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'LOG10'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'log10',
                                                 'argumentCount'    =>    '1'
                                                ),
                'LOGEST'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::LOGEST',
                                                 'argumentCount'    =>    '1-4'
                                                ),
                'LOGINV'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::LOGINV',
                                                 'argumentCount'    =>    '3'
                                                ),
                'LOGNORMDIST'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::LOGNORMDIST',
                                                 'argumentCount'    =>    '3'
                                                ),
                'LOOKUP'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::LOOKUP',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'LOWER'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::LOWERCASE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'MATCH'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::MATCH',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'MAX'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::MAX',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'MAXA'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::MAXA',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'MAXIF'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::MAXIF',
                                                 'argumentCount'    =>    '2+'
                                                ),
                'MDETERM'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::MDETERM',
                                                 'argumentCount'    =>    '1'
                                                ),
                'MDURATION'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '5,6'
                                                ),
                'MEDIAN'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::MEDIAN',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'MEDIANIF'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '2+'
                                                ),
                'MID'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::MID',
                                                 'argumentCount'    =>    '3'
                                                ),
                'MIDB'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::MID',
                                                 'argumentCount'    =>    '3'
                                                ),
                'MIN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::MIN',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'MINA'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::MINA',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'MINIF'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::MINIF',
                                                 'argumentCount'    =>    '2+'
                                                ),
                'MINUTE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::MINUTEOFHOUR',
                                                 'argumentCount'    =>    '1'
                                                ),
                'MINVERSE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::MINVERSE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'MIRR'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::MIRR',
                                                 'argumentCount'    =>    '3'
                                                ),
                'MMULT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::MMULT',
                                                 'argumentCount'    =>    '2'
                                                ),
                'MOD'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::MOD',
                                                 'argumentCount'    =>    '2'
                                                ),
                'MODE'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::MODE',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'MONTH'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::MONTHOFYEAR',
                                                 'argumentCount'    =>    '1'
                                                ),
                'MROUND'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::MROUND',
                                                 'argumentCount'    =>    '2'
                                                ),
                'MULTINOMIAL'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::MULTINOMIAL',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'N'                        => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::N',
                                                 'argumentCount'    =>    '1'
                                                ),
                'NA'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::NA',
                                                 'argumentCount'    =>    '0'
                                                ),
                'NEGBINOMDIST'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::NEGBINOMDIST',
                                                 'argumentCount'    =>    '3'
                                                ),
                'NETWORKDAYS'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::NETWORKDAYS',
                                                 'argumentCount'    =>    '2+'
                                                ),
                'NOMINAL'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::NOMINAL',
                                                 'argumentCount'    =>    '2'
                                                ),
                'NORMDIST'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::NORMDIST',
                                                 'argumentCount'    =>    '4'
                                                ),
                'NORMINV'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::NORMINV',
                                                 'argumentCount'    =>    '3'
                                                ),
                'NORMSDIST'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::NORMSDIST',
                                                 'argumentCount'    =>    '1'
                                                ),
                'NORMSINV'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::NORMSINV',
                                                 'argumentCount'    =>    '1'
                                                ),
                'NOT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOGICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Logical::NOT',
                                                 'argumentCount'    =>    '1'
                                                ),
                'NOW'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::DATETIMENOW',
                                                 'argumentCount'    =>    '0'
                                                ),
                'NPER'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::NPER',
                                                 'argumentCount'    =>    '3-5'
                                                ),
                'NPV'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::NPV',
                                                 'argumentCount'    =>    '2+'
                                                ),
                'OCT2BIN'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::OCTTOBIN',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'OCT2DEC'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::OCTTODEC',
                                                 'argumentCount'    =>    '1'
                                                ),
                'OCT2HEX'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_ENGINEERING,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Engineering::OCTTOHEX',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'ODD'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::ODD',
                                                 'argumentCount'    =>    '1'
                                                ),
                'ODDFPRICE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '8,9'
                                                ),
                'ODDFYIELD'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '8,9'
                                                ),
                'ODDLPRICE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '7,8'
                                                ),
                'ODDLYIELD'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '7,8'
                                                ),
                'OFFSET'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::OFFSET',
                                                 'argumentCount'    =>    '3,5',
                                                 'passCellReference'=>    true,
                                                 'passByReference'    =>    array(true)
                                                ),
                'OR'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOGICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Logical::LOGICAL_OR',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'PEARSON'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::CORREL',
                                                 'argumentCount'    =>    '2'
                                                ),
                'PERCENTILE'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::PERCENTILE',
                                                 'argumentCount'    =>    '2'
                                                ),
                'PERCENTRANK'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::PERCENTRANK',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'PERMUT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::PERMUT',
                                                 'argumentCount'    =>    '2'
                                                ),
                'PHONETIC'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '1'
                                                ),
                'PI'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'pi',
                                                 'argumentCount'    =>    '0'
                                                ),
                'PMT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::PMT',
                                                 'argumentCount'    =>    '3-5'
                                                ),
                'POISSON'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::POISSON',
                                                 'argumentCount'    =>    '3'
                                                ),
                'POWER'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::POWER',
                                                 'argumentCount'    =>    '2'
                                                ),
                'PPMT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::PPMT',
                                                 'argumentCount'    =>    '4-6'
                                                ),
                'PRICE'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::PRICE',
                                                 'argumentCount'    =>    '6,7'
                                                ),
                'PRICEDISC'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::PRICEDISC',
                                                 'argumentCount'    =>    '4,5'
                                                ),
                'PRICEMAT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::PRICEMAT',
                                                 'argumentCount'    =>    '5,6'
                                                ),
                'PROB'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '3,4'
                                                ),
                'PRODUCT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::PRODUCT',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'PROPER'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::PROPERCASE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'PV'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::PV',
                                                 'argumentCount'    =>    '3-5'
                                                ),
                'QUARTILE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::QUARTILE',
                                                 'argumentCount'    =>    '2'
                                                ),
                'QUOTIENT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::QUOTIENT',
                                                 'argumentCount'    =>    '2'
                                                ),
                'RADIANS'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'deg2rad',
                                                 'argumentCount'    =>    '1'
                                                ),
                'RAND'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::RAND',
                                                 'argumentCount'    =>    '0'
                                                ),
                'RANDBETWEEN'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::RAND',
                                                 'argumentCount'    =>    '2'
                                                ),
                'RANK'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::RANK',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'RATE'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::RATE',
                                                 'argumentCount'    =>    '3-6'
                                                ),
                'RECEIVED'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::RECEIVED',
                                                 'argumentCount'    =>    '4-5'
                                                ),
                'REPLACE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::REPLACE',
                                                 'argumentCount'    =>    '4'
                                                ),
                'REPLACEB'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::REPLACE',
                                                 'argumentCount'    =>    '4'
                                                ),
                'REPT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'str_repeat',
                                                 'argumentCount'    =>    '2'
                                                ),
                'RIGHT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::RIGHT',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'RIGHTB'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::RIGHT',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'ROMAN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::ROMAN',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'ROUND'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'round',
                                                 'argumentCount'    =>    '2'
                                                ),
                'ROUNDDOWN'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::ROUNDDOWN',
                                                 'argumentCount'    =>    '2'
                                                ),
                'ROUNDUP'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::ROUNDUP',
                                                 'argumentCount'    =>    '2'
                                                ),
                'ROW'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::ROW',
                                                 'argumentCount'    =>    '-1',
                                                 'passByReference'    =>    array(true)
                                                ),
                'ROWS'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::ROWS',
                                                 'argumentCount'    =>    '1'
                                                ),
                'RSQ'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::RSQ',
                                                 'argumentCount'    =>    '2'
                                                ),
                'RTD'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'SEARCH'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::SEARCHINSENSITIVE',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'SEARCHB'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::SEARCHINSENSITIVE',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'SECOND'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::SECONDOFMINUTE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'SERIESSUM'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::SERIESSUM',
                                                 'argumentCount'    =>    '4'
                                                ),
                'SIGN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::SIGN',
                                                 'argumentCount'    =>    '1'
                                                ),
                'SIN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'sin',
                                                 'argumentCount'    =>    '1'
                                                ),
                'SINH'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'sinh',
                                                 'argumentCount'    =>    '1'
                                                ),
                'SKEW'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::SKEW',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'SLN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::SLN',
                                                 'argumentCount'    =>    '3'
                                                ),
                'SLOPE'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::SLOPE',
                                                 'argumentCount'    =>    '2'
                                                ),
                'SMALL'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::SMALL',
                                                 'argumentCount'    =>    '2'
                                                ),
                'SQRT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'sqrt',
                                                 'argumentCount'    =>    '1'
                                                ),
                'SQRTPI'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::SQRTPI',
                                                 'argumentCount'    =>    '1'
                                                ),
                'STANDARDIZE'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::STANDARDIZE',
                                                 'argumentCount'    =>    '3'
                                                ),
                'STDEV'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::STDEV',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'STDEVA'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::STDEVA',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'STDEVP'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::STDEVP',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'STDEVPA'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::STDEVPA',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'STEYX'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::STEYX',
                                                 'argumentCount'    =>    '2'
                                                ),
                'SUBSTITUTE'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::SUBSTITUTE',
                                                 'argumentCount'    =>    '3,4'
                                                ),
                'SUBTOTAL'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::SUBTOTAL',
                                                 'argumentCount'    =>    '2+'
                                                ),
                'SUM'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::SUM',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'SUMIF'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::SUMIF',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'SUMIFS'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '?'
                                                ),
                'SUMPRODUCT'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::SUMPRODUCT',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'SUMSQ'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::SUMSQ',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'SUMX2MY2'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::SUMX2MY2',
                                                 'argumentCount'    =>    '2'
                                                ),
                'SUMX2PY2'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::SUMX2PY2',
                                                 'argumentCount'    =>    '2'
                                                ),
                'SUMXMY2'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::SUMXMY2',
                                                 'argumentCount'    =>    '2'
                                                ),
                'SYD'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::SYD',
                                                 'argumentCount'    =>    '4'
                                                ),
                'T'                        => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::RETURNSTRING',
                                                 'argumentCount'    =>    '1'
                                                ),
                'TAN'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'tan',
                                                 'argumentCount'    =>    '1'
                                                ),
                'TANH'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'tanh',
                                                 'argumentCount'    =>    '1'
                                                ),
                'TBILLEQ'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::TBILLEQ',
                                                 'argumentCount'    =>    '3'
                                                ),
                'TBILLPRICE'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::TBILLPRICE',
                                                 'argumentCount'    =>    '3'
                                                ),
                'TBILLYIELD'            => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::TBILLYIELD',
                                                 'argumentCount'    =>    '3'
                                                ),
                'TDIST'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::TDIST',
                                                 'argumentCount'    =>    '3'
                                                ),
                'TEXT'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::TEXTFORMAT',
                                                 'argumentCount'    =>    '2'
                                                ),
                'TIME'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::TIME',
                                                 'argumentCount'    =>    '3'
                                                ),
                'TIMEVALUE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::TIMEVALUE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'TINV'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::TINV',
                                                 'argumentCount'    =>    '2'
                                                ),
                'TODAY'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::DATENOW',
                                                 'argumentCount'    =>    '0'
                                                ),
                'TRANSPOSE'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::TRANSPOSE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'TREND'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::TREND',
                                                 'argumentCount'    =>    '1-4'
                                                ),
                'TRIM'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::TRIMSPACES',
                                                 'argumentCount'    =>    '1'
                                                ),
                'TRIMMEAN'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::TRIMMEAN',
                                                 'argumentCount'    =>    '2'
                                                ),
                'TRUE'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOGICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Logical::TRUE',
                                                 'argumentCount'    =>    '0'
                                                ),
                'TRUNC'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_MATH_AND_TRIG,
                                                 'functionCall'        =>    'PHPExcel_Calculation_MathTrig::TRUNC',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'TTEST'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '4'
                                                ),
                'TYPE'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::TYPE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'UPPER'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_TextData::UPPERCASE',
                                                 'argumentCount'    =>    '1'
                                                ),
                'USDOLLAR'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '2'
                                                ),
                'VALUE'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_TEXT_AND_DATA,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '1'
                                                ),
                'VAR'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::VARFunc',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'VARA'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::VARA',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'VARP'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::VARP',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'VARPA'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::VARPA',
                                                 'argumentCount'    =>    '1+'
                                                ),
                'VDB'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '5-7'
                                                ),
                'VERSION'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_INFORMATION,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::VERSION',
                                                 'argumentCount'    =>    '0'
                                                ),
                'VLOOKUP'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_LOOKUP_AND_REFERENCE,
                                                 'functionCall'        =>    'PHPExcel_Calculation_LookupRef::VLOOKUP',
                                                 'argumentCount'    =>    '3,4'
                                                ),
                'WEEKDAY'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::DAYOFWEEK',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'WEEKNUM'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::WEEKOFYEAR',
                                                 'argumentCount'    =>    '1,2'
                                                ),
                'WEIBULL'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::WEIBULL',
                                                 'argumentCount'    =>    '4'
                                                ),
                'WORKDAY'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::WORKDAY',
                                                 'argumentCount'    =>    '2+'
                                                ),
                'XIRR'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::XIRR',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'XNPV'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::XNPV',
                                                 'argumentCount'    =>    '3'
                                                ),
                'YEAR'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::YEAR',
                                                 'argumentCount'    =>    '1'
                                                ),
                'YEARFRAC'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_DATE_AND_TIME,
                                                 'functionCall'        =>    'PHPExcel_Calculation_DateTime::YEARFRAC',
                                                 'argumentCount'    =>    '2,3'
                                                ),
                'YIELD'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Functions::DUMMY',
                                                 'argumentCount'    =>    '6,7'
                                                ),
                'YIELDDISC'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::YIELDDISC',
                                                 'argumentCount'    =>    '4,5'
                                                ),
                'YIELDMAT'                => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_FINANCIAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Financial::YIELDMAT',
                                                 'argumentCount'    =>    '5,6'
                                                ),
                'ZTEST'                    => array('category'            =>    PHPExcel_Calculation_Function::CATEGORY_STATISTICAL,
                                                 'functionCall'        =>    'PHPExcel_Calculation_Statistical::ZTEST',
                                                 'argumentCount'    =>    '2-3'
                                                )
            );


    //    Internal functions used for special control purposes
    private static $_controlFunctions = array(
                'MKMATRIX'    => array('argumentCount'    =>    '*',
                                     'functionCall'        =>    'self::_mkMatrix'
                                    )
            );




    private function __construct() {
        $localeFileDirectory = PHPEXCEL_ROOT.'PHPExcel/locale/';
        foreach (glob($localeFileDirectory.'/*',GLOB_ONLYDIR) as $filename) {
            $filename = substr($filename,strlen($localeFileDirectory)+1);
            if ($filename != 'en') {
                self::$_validLocaleLanguages[] = $filename;
            }
        }

        $setPrecision = (PHP_INT_SIZE == 4) ? 12 : 16;
        $this->_savedPrecision = ini_get('precision');
        if ($this->_savedPrecision < $setPrecision) {
            ini_set('precision',$setPrecision);
        }
    }    //    function __construct()


    public function __destruct() {
        ini_set('precision',$this->_savedPrecision);
    }

    /**
     *    Get an instance of this class
     *
     *    @access    public
     *    @return PHPExcel_Calculation
     */
    public static function getInstance() {
        if (!isset(self::$_instance) || is_null(self::$_instance)) {
            self::$_instance = new PHPExcel_Calculation();
        }

        return self::$_instance;
    }    //    function getInstance()


    /**
     *    Flush the calculation cache for any existing instance of this class
     *        but only if a PHPExcel_Calculation instance exists
     *
     *    @access    public
     *    @return null
     */
    public static function flushInstance() {
        if (isset(self::$_instance) && !is_null(self::$_instance)) {
            self::$_instance->clearCalculationCache();
        }
    }    //    function flushInstance()


    /**
     *    __clone implementation. Cloning should not be allowed in a Singleton!
     *
     *    @access    public
     *    @throws    Exception
     */
    public final function __clone() {
        throw new Exception ('Cloning a Singleton is not allowed!');
    }    //    function __clone()


    /**
     *    Return the locale-specific translation of TRUE
     *
     *    @access    public
     *    @return     string        locale-specific translation of TRUE
     */
    public static function getTRUE() {
        return self::$_localeBoolean['TRUE'];
    }

    /**
     *    Return the locale-specific translation of FALSE
     *
     *    @access    public
     *    @return     string        locale-specific translation of FALSE
     */
    public static function getFALSE() {
        return self::$_localeBoolean['FALSE'];
    }

    /**
     *    Set the Array Return Type (Array or Value of first element in the array)
     *
     *    @access    public
     *    @param     string    $returnType            Array return type
     *    @return     boolean                    Success or failure
     */
    public static function setArrayReturnType($returnType) {
        if (($returnType == self::RETURN_ARRAY_AS_VALUE) ||
            ($returnType == self::RETURN_ARRAY_AS_ERROR) ||
            ($returnType == self::RETURN_ARRAY_AS_ARRAY)) {
            self::$returnArrayAsType = $returnType;
            return true;
        }
        return false;
    }    //    function setExcelCalendar()


    /**
     *    Return the Array Return Type (Array or Value of first element in the array)
     *
     *    @access    public
     *    @return     string        $returnType            Array return type
     */
    public static function getArrayReturnType() {
        return self::$returnArrayAsType;
    }    //    function getExcelCalendar()


    /**
     *    Is calculation caching enabled?
     *
     *    @access    public
     *    @return boolean
     */
    public function getCalculationCacheEnabled() {
        return self::$_calculationCacheEnabled;
    }    //    function getCalculationCacheEnabled()


    /**
     *    Enable/disable calculation cache
     *
     *    @access    public
     *    @param boolean $pValue
     */
    public function setCalculationCacheEnabled($pValue = true) {
        self::$_calculationCacheEnabled = $pValue;
        $this->clearCalculationCache();
    }    //    function setCalculationCacheEnabled()


    /**
     *    Enable calculation cache
     */
    public function enableCalculationCache() {
        $this->setCalculationCacheEnabled(true);
    }    //    function enableCalculationCache()


    /**
     *    Disable calculation cache
     */
    public function disableCalculationCache() {
        $this->setCalculationCacheEnabled(false);
    }    //    function disableCalculationCache()


    /**
     *    Clear calculation cache
     */
    public function clearCalculationCache() {
        self::$_calculationCache = array();
    }    //    function clearCalculationCache()


    /**
     *    Get calculation cache expiration time
     *
     *    @return float
     */
    public function getCalculationCacheExpirationTime() {
        return self::$_calculationCacheExpirationTime;
    }    //    getCalculationCacheExpirationTime()


    /**
     *    Set calculation cache expiration time
     *
     *    @param float $pValue
     */
    public function setCalculationCacheExpirationTime($pValue = 15) {
        self::$_calculationCacheExpirationTime = $pValue;
    }    //    function setCalculationCacheExpirationTime()




    /**
     *    Get the currently defined locale code
     *
     *    @return string
     */
    public function getLocale() {
        return self::$_localeLanguage;
    }    //    function getLocale()


    /**
     *    Set the locale code
     *
     *    @return boolean
     */
    public function setLocale($locale='en_us') {
        //    Identify our locale and language
        $language = $locale = strtolower($locale);
        if (strpos($locale,'_') !== false) {
            list($language) = explode('_',$locale);
        }

        //    Test whether we have any language data for this language (any locale)
        if (in_array($language,self::$_validLocaleLanguages)) {
            //    initialise language/locale settings
            self::$_localeFunctions = array();
            self::$_localeArgumentSeparator = ',';
            self::$_localeBoolean = array('TRUE' => 'TRUE', 'FALSE' => 'FALSE', 'NULL' => 'NULL');
            //    Default is English, if user isn't requesting english, then read the necessary data from the locale files
            if ($locale != 'en_us') {
                //    Search for a file with a list of function names for locale
                $functionNamesFile = PHPEXCEL_ROOT . 'PHPExcel/locale/'.str_replace('_','/',$locale).'/functions';
                if (!file_exists($functionNamesFile)) {
                    //    If there isn't a locale specific function file, look for a language specific function file
                    $functionNamesFile = PHPEXCEL_ROOT . 'PHPExcel/locale/'.$language.'/functions';
                    if (!file_exists($functionNamesFile)) {
                        return false;
                    }
                }
                //    Retrieve the list of locale or language specific function names
                $localeFunctions = file($functionNamesFile,FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
                foreach ($localeFunctions as $localeFunction) {
                    list($localeFunction) = explode('##',$localeFunction);    //    Strip out comments
                    if (strpos($localeFunction,'=') !== false) {
                        list($fName,$lfName) = explode('=',$localeFunction);
                        $fName = trim($fName);
                        $lfName = trim($lfName);
                        if ((isset(self::$_PHPExcelFunctions[$fName])) && ($lfName != '') && ($fName != $lfName)) {
                            self::$_localeFunctions[$fName] = $lfName;
                        }
                    }
                }
                //    Default the TRUE and FALSE constants to the locale names of the TRUE() and FALSE() functions
                if (isset(self::$_localeFunctions['TRUE'])) { self::$_localeBoolean['TRUE'] = self::$_localeFunctions['TRUE']; }
                if (isset(self::$_localeFunctions['FALSE'])) { self::$_localeBoolean['FALSE'] = self::$_localeFunctions['FALSE']; }

                $configFile = PHPEXCEL_ROOT . 'PHPExcel/locale/'.str_replace('_','/',$locale).'/config';
                if (!file_exists($configFile)) {
                    $configFile = PHPEXCEL_ROOT . 'PHPExcel/locale/'.$language.'/config';
                }
                if (file_exists($configFile)) {
                    $localeSettings = file($configFile,FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
                    foreach ($localeSettings as $localeSetting) {
                        list($localeSetting) = explode('##',$localeSetting);    //    Strip out comments
                        if (strpos($localeSetting,'=') !== false) {
                            list($settingName,$settingValue) = explode('=',$localeSetting);
                            $settingName = strtoupper(trim($settingName));
                            switch ($settingName) {
                                case 'ARGUMENTSEPARATOR' :
                                    self::$_localeArgumentSeparator = trim($settingValue);
                                    break;
                            }
                        }
                    }
                }
            }

            self::$functionReplaceFromExcel = self::$functionReplaceToExcel =
            self::$functionReplaceFromLocale = self::$functionReplaceToLocale = null;
            self::$_localeLanguage = $locale;
            return true;
        }
        return false;
    }    //    function setLocale()



    public static function _translateSeparator($fromSeparator,$toSeparator,$formula,&$inBraces) {
        $strlen = mb_strlen($formula);
        for ($i = 0; $i < $strlen; ++$i) {
            $chr = mb_substr($formula,$i,1);
            switch ($chr) {
                case '{' :    $inBraces = true;
                            break;
                case '}' :    $inBraces = false;
                            break;
                case $fromSeparator :
                            if (!$inBraces) {
                                $formula = mb_substr($formula,0,$i).$toSeparator.mb_substr($formula,$i+1);
                            }
            }
        }
        return $formula;
    }

    private static function _translateFormula($from,$to,$formula,$fromSeparator,$toSeparator) {
        //    Convert any Excel function names to the required language
        if (self::$_localeLanguage !== 'en_us') {
            $inBraces = false;
            //    If there is the possibility of braces within a quoted string, then we don't treat those as matrix indicators
            if (strpos($formula,'"') !== false) {
                //    So instead we skip replacing in any quoted strings by only replacing in every other array element after we've exploded
                //        the formula
                $temp = explode('"',$formula);
                $i = false;
                foreach($temp as &$value) {
                    //    Only count/replace in alternating array entries
                    if ($i = !$i) {
                        $value = preg_replace($from,$to,$value);
                        $value = self::_translateSeparator($fromSeparator,$toSeparator,$value,$inBraces);
                    }
                }
                unset($value);
                //    Then rebuild the formula string
                $formula = implode('"',$temp);
            } else {
                //    If there's no quoted strings, then we do a simple count/replace
                $formula = preg_replace($from,$to,$formula);
                $formula = self::_translateSeparator($fromSeparator,$toSeparator,$formula,$inBraces);
            }
        }

        return $formula;
    }

    private static $functionReplaceFromExcel    = null;
    private static $functionReplaceToLocale        = null;

    public function _translateFormulaToLocale($formula) {
        if (is_null(self::$functionReplaceFromExcel)) {
            self::$functionReplaceFromExcel = array();
            foreach(array_keys(self::$_localeFunctions) as $excelFunctionName) {
                self::$functionReplaceFromExcel[] = '/(@?[^\w\.])'.preg_quote($excelFunctionName).'([\s]*\()/Ui';
            }
            foreach(array_keys(self::$_localeBoolean) as $excelBoolean) {
                self::$functionReplaceFromExcel[] = '/(@?[^\w\.])'.preg_quote($excelBoolean).'([^\w\.])/Ui';
            }

        }

        if (is_null(self::$functionReplaceToLocale)) {
            self::$functionReplaceToLocale = array();
            foreach(array_values(self::$_localeFunctions) as $localeFunctionName) {
                self::$functionReplaceToLocale[] = '$1'.trim($localeFunctionName).'$2';
            }
            foreach(array_values(self::$_localeBoolean) as $localeBoolean) {
                self::$functionReplaceToLocale[] = '$1'.trim($localeBoolean).'$2';
            }
        }

        return self::_translateFormula(self::$functionReplaceFromExcel,self::$functionReplaceToLocale,$formula,',',self::$_localeArgumentSeparator);
    }    //    function _translateFormulaToLocale()


    private static $functionReplaceFromLocale    = null;
    private static $functionReplaceToExcel        = null;

    public function _translateFormulaToEnglish($formula) {
        if (is_null(self::$functionReplaceFromLocale)) {
            self::$functionReplaceFromLocale = array();
            foreach(array_values(self::$_localeFunctions) as $localeFunctionName) {
                self::$functionReplaceFromLocale[] = '/(@?[^\w\.])'.preg_quote($localeFunctionName).'([\s]*\()/Ui';
            }
            foreach(array_values(self::$_localeBoolean) as $excelBoolean) {
                self::$functionReplaceFromLocale[] = '/(@?[^\w\.])'.preg_quote($excelBoolean).'([^\w\.])/Ui';
            }
        }

        if (is_null(self::$functionReplaceToExcel)) {
            self::$functionReplaceToExcel = array();
            foreach(array_keys(self::$_localeFunctions) as $excelFunctionName) {
                self::$functionReplaceToExcel[] = '$1'.trim($excelFunctionName).'$2';
            }
            foreach(array_keys(self::$_localeBoolean) as $excelBoolean) {
                self::$functionReplaceToExcel[] = '$1'.trim($excelBoolean).'$2';
            }
        }

        return self::_translateFormula(self::$functionReplaceFromLocale,self::$functionReplaceToExcel,$formula,self::$_localeArgumentSeparator,',');
    }    //    function _translateFormulaToEnglish()


    public static function _localeFunc($function) {
        if (self::$_localeLanguage !== 'en_us') {
            $functionName = trim($function,'(');
            if (isset(self::$_localeFunctions[$functionName])) {
                $brace = ($functionName != $function);
                $function = self::$_localeFunctions[$functionName];
                if ($brace) { $function .= '('; }
            }
        }
        return $function;
    }




    /**
     *    Wrap string values in quotes
     *
     *    @param mixed $value
     *    @return mixed
     */
    public static function _wrapResult($value) {
        if (is_string($value)) {
            //    Error values cannot be "wrapped"
            if (preg_match('/^'.self::CALCULATION_REGEXP_ERROR.'$/i', $value, $match)) {
                //    Return Excel errors "as is"
                return $value;
            }
            //    Return strings wrapped in quotes
            return '"'.$value.'"';
        //    Convert numeric errors to NaN error
        } else if((is_float($value)) && ((is_nan($value)) || (is_infinite($value)))) {
            return PHPExcel_Calculation_Functions::NaN();
        }

        return $value;
    }    //    function _wrapResult()


    /**
     *    Remove quotes used as a wrapper to identify string values
     *
     *    @param mixed $value
     *    @return mixed
     */
    public static function _unwrapResult($value) {
        if (is_string($value)) {
            if ((isset($value{0})) && ($value{0} == '"') && (substr($value,-1) == '"')) {
                return substr($value,1,-1);
            }
        //    Convert numeric errors to NaN error
        } else if((is_float($value)) && ((is_nan($value)) || (is_infinite($value)))) {
            return PHPExcel_Calculation_Functions::NaN();
        }
        return $value;
    }    //    function _unwrapResult()




    /**
     *    Calculate cell value (using formula from a cell ID)
     *    Retained for backward compatibility
     *
     *    @access    public
     *    @param    PHPExcel_Cell    $pCell    Cell to calculate
     *    @return    mixed
     *    @throws    Exception
     */
    public function calculate(PHPExcel_Cell $pCell = null) {
        try {
            return $this->calculateCellValue($pCell);
        } catch (Exception $e) {
            throw(new Exception($e->getMessage()));
        }
    }    //    function calculate()


    /**
     *    Calculate the value of a cell formula
     *
     *    @access    public
     *    @param    PHPExcel_Cell    $pCell        Cell to calculate
     *    @param    Boolean            $resetLog    Flag indicating whether the debug log should be reset or not
     *    @return    mixed
     *    @throws    Exception
     */
    public function calculateCellValue(PHPExcel_Cell $pCell = null, $resetLog = true) {
        if ($resetLog) {
            //    Initialise the logging settings if requested
            $this->formulaError = null;
            $this->debugLog = $this->debugLogStack = array();
            $this->_cyclicFormulaCount = 1;

            $returnArrayAsType = self::$returnArrayAsType;
            self::$returnArrayAsType = self::RETURN_ARRAY_AS_ARRAY;
        }

        //    Read the formula from the cell
        if (is_null($pCell)) {
            return null;
        }

        if ($resetLog) {
            self::$returnArrayAsType = $returnArrayAsType;
        }
        //    Execute the calculation for the cell formula
        try {
            $result = self::_unwrapResult($this->_calculateFormulaValue($pCell->getValue(), $pCell->getCoordinate(), $pCell));
        } catch (Exception $e) {
            throw(new Exception($e->getMessage()));
        }

        if ((is_array($result)) && (self::$returnArrayAsType != self::RETURN_ARRAY_AS_ARRAY)) {
            $testResult = PHPExcel_Calculation_Functions::flattenArray($result);
            if (self::$returnArrayAsType == self::RETURN_ARRAY_AS_ERROR) {
                return PHPExcel_Calculation_Functions::VALUE();
            }
            //    If there's only a single cell in the array, then we allow it
            if (count($testResult) != 1) {
                //    If keys are numeric, then it's a matrix result rather than a cell range result, so we permit it
                $r = array_keys($result);
                $r = array_shift($r);
                if (!is_numeric($r)) { return PHPExcel_Calculation_Functions::VALUE(); }
                if (is_array($result[$r])) {
                    $c = array_keys($result[$r]);
                    $c = array_shift($c);
                    if (!is_numeric($c)) {
                        return PHPExcel_Calculation_Functions::VALUE();
                    }
                }
            }
            $result = array_shift($testResult);
        }

        if (is_null($result)) {
            return 0;
        } elseif((is_float($result)) && ((is_nan($result)) || (is_infinite($result)))) {
            return PHPExcel_Calculation_Functions::NaN();
        }
        return $result;
    }    //    function calculateCellValue(


    /**
     *    Validate and parse a formula string
     *
     *    @param    string        $formula        Formula to parse
     *    @return    array
     *    @throws    Exception
     */
    public function parseFormula($formula) {
        //    Basic validation that this is indeed a formula
        //    We return an empty array if not
        $formula = trim($formula);
        if ((!isset($formula{0})) || ($formula{0} != '=')) return array();
        $formula = ltrim(substr($formula,1));
        if (!isset($formula{0})) return array();

        //    Parse the formula and return the token stack
        return $this->_parseFormula($formula);
    }    //    function parseFormula()


    /**
     *    Calculate the value of a formula
     *
     *    @param    string        $formula        Formula to parse
     *    @return    mixed
     *    @throws    Exception
     */
    public function calculateFormula($formula, $cellID=null, PHPExcel_Cell $pCell = null) {
        //    Initialise the logging settings
        $this->formulaError = null;
        $this->debugLog = $this->debugLogStack = array();

        //    Disable calculation cacheing because it only applies to cell calculations, not straight formulae
        //    But don't actually flush any cache
        $resetCache = $this->getCalculationCacheEnabled();
        self::$_calculationCacheEnabled = false;
        //    Execute the calculation
        try {
            $result = self::_unwrapResult($this->_calculateFormulaValue($formula, $cellID, $pCell));
        } catch (Exception $e) {
            throw(new Exception($e->getMessage()));
        }

        //    Reset calculation cacheing to its previous state
        self::$_calculationCacheEnabled = $resetCache;

        return $result;
    }    //    function calculateFormula()


    /**
     *    Parse a cell formula and calculate its value
     *
     *    @param    string            $formula    The formula to parse and calculate
     *    @param    string            $cellID        The ID (e.g. A3) of the cell that we are calculating
     *    @param    PHPExcel_Cell    $pCell        Cell to calculate
     *    @return    mixed
     *    @throws    Exception
     */
    public function _calculateFormulaValue($formula, $cellID=null, PHPExcel_Cell $pCell = null) {
//        echo '<b>'.$cellID.'</b><br />';
        $cellValue = '';

        //    Basic validation that this is indeed a formula
        //    We simply return the "cell value" (formula) if not
        $formula = trim($formula);
        if ($formula{0} != '=') return self::_wrapResult($formula);
        $formula = ltrim(substr($formula,1));
        if (!isset($formula{0})) return self::_wrapResult($formula);

        $wsTitle = "\x00Wrk";
        if (!is_null($pCell)) {
            $pCellParent = $pCell->getParent();
            if (!is_null($pCellParent)) {
                $wsTitle = $pCellParent->getTitle();
            }
        }
        // Is calculation cacheing enabled?
        if (!is_null($cellID)) {
            if (self::$_calculationCacheEnabled) {
                // Is the value present in calculation cache?
//                echo 'Testing cache value<br />';
                if (isset(self::$_calculationCache[$wsTitle][$cellID])) {
//                    echo 'Value is in cache<br />';
                    $this->_writeDebug('Testing cache value for cell '.$cellID);
                    //    Is cache still valid?
                    if ((microtime(true) - self::$_calculationCache[$wsTitle][$cellID]['time']) < self::$_calculationCacheExpirationTime) {
//                        echo 'Cache time is still valid<br />';
                        $this->_writeDebug('Retrieving value for '.$cellID.' from cache');
                        // Return the cached result
                        $returnValue = self::$_calculationCache[$wsTitle][$cellID]['data'];
//                        echo 'Retrieving data value of '.$returnValue.' for '.$cellID.' from cache<br />';
                        if (is_array($returnValue)) {
                            $returnValue = PHPExcel_Calculation_Functions::flattenArray($returnValue);
                            return array_shift($returnValue);
                        }
                        return $returnValue;
                    } else {
//                        echo 'Cache has expired<br />';
                        $this->_writeDebug('Cache value for '.$cellID.' has expired');
                        //    Clear the cache if it's no longer valid
                        unset(self::$_calculationCache[$wsTitle][$cellID]);
                    }
                }
            }
        }

        if ((in_array($wsTitle.'!'.$cellID,$this->debugLogStack)) && ($wsTitle != "\x00Wrk")) {
            if ($this->cyclicFormulaCount <= 0) {
                return $this->_raiseFormulaError('Cyclic Reference in Formula');
            } elseif (($this->_cyclicFormulaCount >= $this->cyclicFormulaCount) &&
                      ($this->_cyclicFormulaCell == $wsTitle.'!'.$cellID)) {
                return $cellValue;
            } elseif ($this->_cyclicFormulaCell == $wsTitle.'!'.$cellID) {
                ++$this->_cyclicFormulaCount;
                if ($this->_cyclicFormulaCount >= $this->cyclicFormulaCount) {
                    return $cellValue;
                }
            } elseif ($this->_cyclicFormulaCell == '') {
                $this->_cyclicFormulaCell = $wsTitle.'!'.$cellID;
                if ($this->_cyclicFormulaCount >= $this->cyclicFormulaCount) {
                    return $cellValue;
                }
            }
        }
        $this->debugLogStack[] = $wsTitle.'!'.$cellID;
        //    Parse the formula onto the token stack and calculate the value
        $cellValue = $this->_processTokenStack($this->_parseFormula($formula, $pCell), $cellID, $pCell);
        array_pop($this->debugLogStack);

        // Save to calculation cache
        if (!is_null($cellID)) {
            if (self::$_calculationCacheEnabled) {
                self::$_calculationCache[$wsTitle][$cellID]['time'] = microtime(true);
                self::$_calculationCache[$wsTitle][$cellID]['data'] = $cellValue;
            }
        }

        //    Return the calculated value
        return $cellValue;
    }    //    function _calculateFormulaValue()


    /**
     *    Ensure that paired matrix operands are both matrices and of the same size
     *
     *    @param    mixed        &$operand1    First matrix operand
     *    @param    mixed        &$operand2    Second matrix operand
     *    @param    integer        $resize        Flag indicating whether the matrices should be resized to match
     *                                        and (if so), whether the smaller dimension should grow or the
     *                                        larger should shrink.
     *                                            0 = no resize
     *                                            1 = shrink to fit
     *                                            2 = extend to fit
     */
    private static function _checkMatrixOperands(&$operand1,&$operand2,$resize = 1) {
        //    Examine each of the two operands, and turn them into an array if they aren't one already
        //    Note that this function should only be called if one or both of the operand is already an array
        if (!is_array($operand1)) {
            list($matrixRows,$matrixColumns) = self::_getMatrixDimensions($operand2);
            $operand1 = array_fill(0,$matrixRows,array_fill(0,$matrixColumns,$operand1));
            $resize = 0;
        } elseif (!is_array($operand2)) {
            list($matrixRows,$matrixColumns) = self::_getMatrixDimensions($operand1);
            $operand2 = array_fill(0,$matrixRows,array_fill(0,$matrixColumns,$operand2));
            $resize = 0;
        }

        list($matrix1Rows,$matrix1Columns) = self::_getMatrixDimensions($operand1);
        list($matrix2Rows,$matrix2Columns) = self::_getMatrixDimensions($operand2);
        if (($matrix1Rows == $matrix2Columns) && ($matrix2Rows == $matrix1Columns)) {
            $resize = 1;
        }

        if ($resize == 2) {
            //    Given two matrices of (potentially) unequal size, convert the smaller in each dimension to match the larger
            self::_resizeMatricesExtend($operand1,$operand2,$matrix1Rows,$matrix1Columns,$matrix2Rows,$matrix2Columns);
        } elseif ($resize == 1) {
            //    Given two matrices of (potentially) unequal size, convert the larger in each dimension to match the smaller
            self::_resizeMatricesShrink($operand1,$operand2,$matrix1Rows,$matrix1Columns,$matrix2Rows,$matrix2Columns);
        }
        return array( $matrix1Rows,$matrix1Columns,$matrix2Rows,$matrix2Columns);
    }    //    function _checkMatrixOperands()


    /**
     *    Read the dimensions of a matrix, and re-index it with straight numeric keys starting from row 0, column 0
     *
     *    @param    mixed        &$matrix        matrix operand
     *    @return    array        An array comprising the number of rows, and number of columns
     */
    public static function _getMatrixDimensions(&$matrix) {
        $matrixRows = count($matrix);
        $matrixColumns = 0;
        foreach($matrix as $rowKey => $rowValue) {
            $matrixColumns = max(count($rowValue),$matrixColumns);
            if (!is_array($rowValue)) {
                $matrix[$rowKey] = array($rowValue);
            } else {
                $matrix[$rowKey] = array_values($rowValue);
            }
        }
        $matrix = array_values($matrix);
        return array($matrixRows,$matrixColumns);
    }    //    function _getMatrixDimensions()


    /**
     *    Ensure that paired matrix operands are both matrices of the same size
     *
     *    @param    mixed        &$matrix1    First matrix operand
     *    @param    mixed        &$matrix2    Second matrix operand
     */
    private static function _resizeMatricesShrink(&$matrix1,&$matrix2,$matrix1Rows,$matrix1Columns,$matrix2Rows,$matrix2Columns) {
        if (($matrix2Columns < $matrix1Columns) || ($matrix2Rows < $matrix1Rows)) {
            if ($matrix2Columns < $matrix1Columns) {
                for ($i = 0; $i < $matrix1Rows; ++$i) {
                    for ($j = $matrix2Columns; $j < $matrix1Columns; ++$j) {
                        unset($matrix1[$i][$j]);
                    }
                }
            }
            if ($matrix2Rows < $matrix1Rows) {
                for ($i = $matrix2Rows; $i < $matrix1Rows; ++$i) {
                    unset($matrix1[$i]);
                }
            }
        }

        if (($matrix1Columns < $matrix2Columns) || ($matrix1Rows < $matrix2Rows)) {
            if ($matrix1Columns < $matrix2Columns) {
                for ($i = 0; $i < $matrix2Rows; ++$i) {
                    for ($j = $matrix1Columns; $j < $matrix2Columns; ++$j) {
                        unset($matrix2[$i][$j]);
                    }
                }
            }
            if ($matrix1Rows < $matrix2Rows) {
                for ($i = $matrix1Rows; $i < $matrix2Rows; ++$i) {
                    unset($matrix2[$i]);
                }
            }
        }
    }    //    function _resizeMatricesShrink()


    /**
     *    Ensure that paired matrix operands are both matrices of the same size
     *
     *    @param    mixed        &$matrix1    First matrix operand
     *    @param    mixed        &$matrix2    Second matrix operand
     */
    private static function _resizeMatricesExtend(&$matrix1,&$matrix2,$matrix1Rows,$matrix1Columns,$matrix2Rows,$matrix2Columns) {
        if (($matrix2Columns < $matrix1Columns) || ($matrix2Rows < $matrix1Rows)) {
            if ($matrix2Columns < $matrix1Columns) {
                for ($i = 0; $i < $matrix2Rows; ++$i) {
                    $x = $matrix2[$i][$matrix2Columns-1];
                    for ($j = $matrix2Columns; $j < $matrix1Columns; ++$j) {
                        $matrix2[$i][$j] = $x;
                    }
                }
            }
            if ($matrix2Rows < $matrix1Rows) {
                $x = $matrix2[$matrix2Rows-1];
                for ($i = 0; $i < $matrix1Rows; ++$i) {
                    $matrix2[$i] = $x;
                }
            }
        }

        if (($matrix1Columns < $matrix2Columns) || ($matrix1Rows < $matrix2Rows)) {
            if ($matrix1Columns < $matrix2Columns) {
                for ($i = 0; $i < $matrix1Rows; ++$i) {
                    $x = $matrix1[$i][$matrix1Columns-1];
                    for ($j = $matrix1Columns; $j < $matrix2Columns; ++$j) {
                        $matrix1[$i][$j] = $x;
                    }
                }
            }
            if ($matrix1Rows < $matrix2Rows) {
                $x = $matrix1[$matrix1Rows-1];
                for ($i = 0; $i < $matrix2Rows; ++$i) {
                    $matrix1[$i] = $x;
                }
            }
        }
    }    //    function _resizeMatricesExtend()


    /**
     *    Format details of an operand for display in the log (based on operand type)
     *
     *    @param    mixed        $value    First matrix operand
     *    @return    mixed
     */
    private function _showValue($value) {
        if ($this->writeDebugLog) {
            $testArray = PHPExcel_Calculation_Functions::flattenArray($value);
            if (count($testArray) == 1) {
                $value = array_pop($testArray);
            }

            if (is_array($value)) {
                $returnMatrix = array();
                $pad = $rpad = ', ';
                foreach($value as $row) {
                    if (is_array($row)) {
                        $returnMatrix[] = implode($pad,$row);
                        $rpad = '; ';
                    } else {
                        $returnMatrix[] = $row;
                    }
                }
                return '{ '.implode($rpad,$returnMatrix).' }';
            } elseif(is_bool($value)) {
                return ($value) ? self::$_localeBoolean['TRUE'] : self::$_localeBoolean['FALSE'];
            }
        }
        return $value;
    }    //    function _showValue()


    /**
     *    Format type and details of an operand for display in the log (based on operand type)
     *
     *    @param    mixed        $value    First matrix operand
     *    @return    mixed
     */
    private function _showTypeDetails($value) {
        if ($this->writeDebugLog) {
            $testArray = PHPExcel_Calculation_Functions::flattenArray($value);
            if (count($testArray) == 1) {
                $value = array_pop($testArray);
            }

            if (is_null($value)) {
                return 'a null value';
            } elseif (is_float($value)) {
                $typeString = 'a floating point number';
            } elseif(is_int($value)) {
                $typeString = 'an integer number';
            } elseif(is_bool($value)) {
                $typeString = 'a boolean';
            } elseif(is_array($value)) {
                $typeString = 'a matrix';
            } else {
                if ($value == '') {
                    return 'an empty string';
                } elseif ($value{0} == '#') {
                    return 'a '.$value.' error';
                } else {
                    $typeString = 'a string';
                }
            }
            return $typeString.' with a value of '.$this->_showValue($value);
        }
    }    //    function _showTypeDetails()


    private static function _convertMatrixReferences($formula) {
        static $matrixReplaceFrom = array('{',';','}');
        static $matrixReplaceTo = array('MKMATRIX(MKMATRIX(','),MKMATRIX(','))');

        //    Convert any Excel matrix references to the MKMATRIX() function
        if (strpos($formula,'{') !== false) {
            //    If there is the possibility of braces within a quoted string, then we don't treat those as matrix indicators
            if (strpos($formula,'"') !== false) {
                //    So instead we skip replacing in any quoted strings by only replacing in every other array element after we've exploded
                //        the formula
                $temp = explode('"',$formula);
                //    Open and Closed counts used for trapping mismatched braces in the formula
                $openCount = $closeCount = 0;
                $i = false;
                foreach($temp as &$value) {
                    //    Only count/replace in alternating array entries
                    if ($i = !$i) {
                        $openCount += substr_count($value,'{');
                        $closeCount += substr_count($value,'}');
                        $value = str_replace($matrixReplaceFrom,$matrixReplaceTo,$value);
                    }
                }
                unset($value);
                //    Then rebuild the formula string
                $formula = implode('"',$temp);
            } else {
                //    If there's no quoted strings, then we do a simple count/replace
                $openCount = substr_count($formula,'{');
                $closeCount = substr_count($formula,'}');
                $formula = str_replace($matrixReplaceFrom,$matrixReplaceTo,$formula);
            }
            //    Trap for mismatched braces and trigger an appropriate error
            if ($openCount < $closeCount) {
                if ($openCount > 0) {
                    return $this->_raiseFormulaError("Formula Error: Mismatched matrix braces '}'");
                } else {
                    return $this->_raiseFormulaError("Formula Error: Unexpected '}' encountered");
                }
            } elseif ($openCount > $closeCount) {
                if ($closeCount > 0) {
                    return $this->_raiseFormulaError("Formula Error: Mismatched matrix braces '{'");
                } else {
                    return $this->_raiseFormulaError("Formula Error: Unexpected '{' encountered");
                }
            }
        }

        return $formula;
    }    //    function _convertMatrixReferences()


    private static function _mkMatrix() {
        return func_get_args();
    }    //    function _mkMatrix()


    // Convert infix to postfix notation
    private function _parseFormula($formula, PHPExcel_Cell $pCell = null) {
        if (($formula = self::_convertMatrixReferences(trim($formula))) === false) {
            return false;
        }

        //    If we're using cell caching, then $pCell may well be flushed back to the cache (which detaches the parent worksheet),
        //        so we store the parent worksheet so that we can re-attach it when necessary
        $pCellParent = (!is_null($pCell)) ? $pCell->getParent() : null;

        //    Binary Operators
        //    These operators always work on two values
        //    Array key is the operator, the value indicates whether this is a left or right associative operator
        $operatorAssociativity    = array('^' => 0,                                                            //    Exponentiation
                                        '*' => 0, '/' => 0,                                                 //    Multiplication and Division
                                        '+' => 0, '-' => 0,                                                    //    Addition and Subtraction
                                        '&' => 0,                                                            //    Concatenation
                                        '|' => 0, ':' => 0,                                                    //    Intersect and Range
                                        '>' => 0, '<' => 0, '=' => 0, '>=' => 0, '<=' => 0, '<>' => 0        //    Comparison
                                       );
        //    Comparison (Boolean) Operators
        //    These operators work on two values, but always return a boolean result
        $comparisonOperators    = array('>' => true, '<' => true, '=' => true, '>=' => true, '<=' => true, '<>' => true);

        //    Operator Precedence
        //    This list includes all valid operators, whether binary (including boolean) or unary (such as %)
        //    Array key is the operator, the value is its precedence
        $operatorPrecedence    = array(':' => 8,                                                                //    Range
                                    '|' => 7,                                                                //    Intersect
                                    '~' => 6,                                                                //    Negation
                                    '%' => 5,                                                                //    Percentage
                                    '^' => 4,                                                                //    Exponentiation
                                    '*' => 3, '/' => 3,                                                     //    Multiplication and Division
                                    '+' => 2, '-' => 2,                                                        //    Addition and Subtraction
                                    '&' => 1,                                                                //    Concatenation
                                    '>' => 0, '<' => 0, '=' => 0, '>=' => 0, '<=' => 0, '<>' => 0            //    Comparison
                                   );

        $regexpMatchString = '/^('.self::CALCULATION_REGEXP_FUNCTION.
                               '|'.self::CALCULATION_REGEXP_NUMBER.
                               '|'.self::CALCULATION_REGEXP_STRING.
                               '|'.self::CALCULATION_REGEXP_OPENBRACE.
                               '|'.self::CALCULATION_REGEXP_CELLREF.
                               '|'.self::CALCULATION_REGEXP_NAMEDRANGE.
                               '|'.self::CALCULATION_REGEXP_ERROR.
                             ')/si';

        //    Start with initialisation
        $index = 0;
        $stack = new PHPExcel_Token_Stack;
        $output = array();
        $expectingOperator = false;                    //    We use this test in syntax-checking the expression to determine when a
                                                    //        - is a negation or + is a positive operator rather than an operation
        $expectingOperand = false;                    //    We use this test in syntax-checking the expression to determine whether an operand
                                                    //        should be null in a function call
        //    The guts of the lexical parser
        //    Loop through the formula extracting each operator and operand in turn
        while(true) {
//            echo 'Assessing Expression <b>'.substr($formula, $index).'</b><br />';
            $opCharacter = $formula{$index};    //    Get the first character of the value at the current index position
//            echo 'Initial character of expression block is '.$opCharacter.'<br />';
            if ((isset($comparisonOperators[$opCharacter])) && (strlen($formula) > $index) && (isset($comparisonOperators[$formula{$index+1}]))) {
                $opCharacter .= $formula{++$index};
//                echo 'Initial character of expression block is comparison operator '.$opCharacter.'<br />';
            }

            //    Find out if we're currently at the beginning of a number, variable, cell reference, function, parenthesis or operand
            $isOperandOrFunction = preg_match($regexpMatchString, substr($formula, $index), $match);
//            echo '$isOperandOrFunction is '.(($isOperandOrFunction) ? 'True' : 'False').'<br />';
//            var_dump($match);

            if ($opCharacter == '-' && !$expectingOperator) {                //    Is it a negation instead of a minus?
//                echo 'Element is a Negation operator<br />';
                $stack->push('Unary Operator','~');                            //    Put a negation on the stack
                ++$index;                                                    //        and drop the negation symbol
            } elseif ($opCharacter == '%' && $expectingOperator) {
//                echo 'Element is a Percentage operator<br />';
                $stack->push('Unary Operator','%');                            //    Put a percentage on the stack
                ++$index;
            } elseif ($opCharacter == '+' && !$expectingOperator) {            //    Positive (unary plus rather than binary operator plus) can be discarded?
//                echo 'Element is a Positive number, not Plus operator<br />';
                ++$index;                                                    //    Drop the redundant plus symbol
            } elseif ((($opCharacter == '~') || ($opCharacter == '|')) && (!$isOperandOrFunction)) {    //    We have to explicitly deny a tilde or pipe, because they are legal
                return $this->_raiseFormulaError("Formula Error: Illegal character '~'");                //        on the stack but not in the input expression

            } elseif ((isset(self::$_operators[$opCharacter]) or $isOperandOrFunction) && $expectingOperator) {    //    Are we putting an operator on the stack?
//                echo 'Element with value '.$opCharacter.' is an Operator<br />';
                while($stack->count() > 0 &&
                    ($o2 = $stack->last()) &&
                    isset(self::$_operators[$o2['value']]) &&
                    @($operatorAssociativity[$opCharacter] ? $operatorPrecedence[$opCharacter] < $operatorPrecedence[$o2['value']] : $operatorPrecedence[$opCharacter] <= $operatorPrecedence[$o2['value']])) {
                    $output[] = $stack->pop();                                //    Swap operands and higher precedence operators from the stack to the output
                }
                $stack->push('Binary Operator',$opCharacter);    //    Finally put our current operator onto the stack
                ++$index;
                $expectingOperator = false;

            } elseif ($opCharacter == ')' && $expectingOperator) {            //    Are we expecting to close a parenthesis?
//                echo 'Element is a Closing bracket<br />';
                $expectingOperand = false;
                while (($o2 = $stack->pop()) && $o2['value'] != '(') {        //    Pop off the stack back to the last (
                    if (is_null($o2)) return $this->_raiseFormulaError('Formula Error: Unexpected closing brace ")"');
                    else $output[] = $o2;
                }
                $d = $stack->last(2);
                if (preg_match('/^'.self::CALCULATION_REGEXP_FUNCTION.'$/i', $d['value'], $matches)) {    //    Did this parenthesis just close a function?
                    $functionName = $matches[1];                                        //    Get the function name
//                    echo 'Closed Function is '.$functionName.'<br />';
                    $d = $stack->pop();
                    $argumentCount = $d['value'];        //    See how many arguments there were (argument count is the next value stored on the stack)
//                    if ($argumentCount == 0) {
//                        echo 'With no arguments<br />';
//                    } elseif ($argumentCount == 1) {
//                        echo 'With 1 argument<br />';
//                    } else {
//                        echo 'With '.$argumentCount.' arguments<br />';
//                    }
                    $output[] = $d;                        //    Dump the argument count on the output
                    $output[] = $stack->pop();            //    Pop the function and push onto the output
                    if (isset(self::$_controlFunctions[$functionName])) {
//                        echo 'Built-in function '.$functionName.'<br />';
                        $expectedArgumentCount = self::$_controlFunctions[$functionName]['argumentCount'];
                        $functionCall = self::$_controlFunctions[$functionName]['functionCall'];
                    } elseif (isset(self::$_PHPExcelFunctions[$functionName])) {
//                        echo 'PHPExcel function '.$functionName.'<br />';
                        $expectedArgumentCount = self::$_PHPExcelFunctions[$functionName]['argumentCount'];
                        $functionCall = self::$_PHPExcelFunctions[$functionName]['functionCall'];
                    } else {    // did we somehow push a non-function on the stack? this should never happen
                        return $this->_raiseFormulaError("Formula Error: Internal error, non-function on stack");
                    }
                    //    Check the argument count
                    $argumentCountError = false;
                    if (is_numeric($expectedArgumentCount)) {
                        if ($expectedArgumentCount < 0) {
//                            echo '$expectedArgumentCount is between 0 and '.abs($expectedArgumentCount).'<br />';
                            if ($argumentCount > abs($expectedArgumentCount)) {
                                $argumentCountError = true;
                                $expectedArgumentCountString = 'no more than '.abs($expectedArgumentCount);
                            }
                        } else {
//                            echo '$expectedArgumentCount is numeric '.$expectedArgumentCount.'<br />';
                            if ($argumentCount != $expectedArgumentCount) {
                                $argumentCountError = true;
                                $expectedArgumentCountString = $expectedArgumentCount;
                            }
                        }
                    } elseif ($expectedArgumentCount != '*') {
                        $isOperandOrFunction = preg_match('/(\d*)([-+,])(\d*)/',$expectedArgumentCount,$argMatch);
//                        print_r($argMatch);
//                        echo '<br />';
                        switch ($argMatch[2]) {
                            case '+' :
                                if ($argumentCount < $argMatch[1]) {
                                    $argumentCountError = true;
                                    $expectedArgumentCountString = $argMatch[1].' or more ';
                                }
                                break;
                            case '-' :
                                if (($argumentCount < $argMatch[1]) || ($argumentCount > $argMatch[3])) {
                                    $argumentCountError = true;
                                    $expectedArgumentCountString = 'between '.$argMatch[1].' and '.$argMatch[3];
                                }
                                break;
                            case ',' :
                                if (($argumentCount != $argMatch[1]) && ($argumentCount != $argMatch[3])) {
                                    $argumentCountError = true;
                                    $expectedArgumentCountString = 'either '.$argMatch[1].' or '.$argMatch[3];
                                }
                                break;
                        }
                    }
                    if ($argumentCountError) {
                        return $this->_raiseFormulaError("Formula Error: Wrong number of arguments for $functionName() function: $argumentCount given, ".$expectedArgumentCountString." expected");
                    }
                }
                ++$index;

            } elseif ($opCharacter == ',') {            //    Is this the separator for function arguments?
//                echo 'Element is a Function argument separator<br />';
                while (($o2 = $stack->pop()) && $o2['value'] != '(') {        //    Pop off the stack back to the last (
                    if (is_null($o2)) return $this->_raiseFormulaError("Formula Error: Unexpected ,");
                    else $output[] = $o2;    // pop the argument expression stuff and push onto the output
                }
                //    If we've a comma when we're expecting an operand, then what we actually have is a null operand;
                //        so push a null onto the stack
                if (($expectingOperand) || (!$expectingOperator)) {
                    $output[] = array('type' => 'NULL Value', 'value' => self::$_ExcelConstants['NULL'], 'reference' => null);
                }
                // make sure there was a function
                $d = $stack->last(2);
                if (!preg_match('/^'.self::CALCULATION_REGEXP_FUNCTION.'$/i', $d['value'], $matches))
                    return $this->_raiseFormulaError("Formula Error: Unexpected ,");
                $d = $stack->pop();
                $stack->push($d['type'],++$d['value'],$d['reference']);    // increment the argument count
                $stack->push('Brace', '(');    // put the ( back on, we'll need to pop back to it again
                $expectingOperator = false;
                $expectingOperand = true;
                ++$index;

            } elseif ($opCharacter == '(' && !$expectingOperator) {
//                echo 'Element is an Opening Bracket<br />';
                $stack->push('Brace', '(');
                ++$index;

            } elseif ($isOperandOrFunction && !$expectingOperator) {    // do we now have a function/variable/number?
                $expectingOperator = true;
                $expectingOperand = false;
                $val = $match[1];
                $length = strlen($val);
//                echo 'Element with value '.$val.' is an Operand, Variable, Constant, String, Number, Cell Reference or Function<br />';

                if (preg_match('/^'.self::CALCULATION_REGEXP_FUNCTION.'$/i', $val, $matches)) {
                    $val = preg_replace('/\s/','',$val);
//                    echo 'Element '.$val.' is a Function<br />';
                    if (isset(self::$_PHPExcelFunctions[strtoupper($matches[1])]) || isset(self::$_controlFunctions[strtoupper($matches[1])])) {    // it's a function
                        $stack->push('Function', strtoupper($val));
                        $ax = preg_match('/^\s*(\s*\))/i', substr($formula, $index+$length), $amatch);
                        if ($ax) {
                            $stack->push('Operand Count for Function '.self::_localeFunc(strtoupper($val)).')', 0);
                            $expectingOperator = true;
                        } else {
                            $stack->push('Operand Count for Function '.self::_localeFunc(strtoupper($val)).')', 1);
                            $expectingOperator = false;
                        }
                        $stack->push('Brace', '(');
                    } else {    // it's a var w/ implicit multiplication
                        $output[] = array('type' => 'Value', 'value' => $matches[1], 'reference' => null);
                    }
                } elseif (preg_match('/^'.self::CALCULATION_REGEXP_CELLREF.'$/i', $val, $matches)) {
//                    echo 'Element '.$val.' is a Cell reference<br />';
                    //    Watch for this case-change when modifying to allow cell references in different worksheets...
                    //    Should only be applied to the actual cell column, not the worksheet name

                    //    If the last entry on the stack was a : operator, then we have a cell range reference
                    $testPrevOp = $stack->last(1);
                    if ($testPrevOp['value'] == ':') {
                        //    If we have a worksheet reference, then we're playing with a 3D reference
                        if ($matches[2] == '') {
                            //    Otherwise, we 'inherit' the worksheet reference from the start cell reference
                            //    The start of the cell range reference should be the last entry in $output
                            $startCellRef = $output[count($output)-1]['value'];
                            preg_match('/^'.self::CALCULATION_REGEXP_CELLREF.'$/i', $startCellRef, $startMatches);
                            if ($startMatches[2] > '') {
                                $val = $startMatches[2].'!'.$val;
                            }
                        } else {
                            return $this->_raiseFormulaError("3D Range references are not yet supported");
                        }
                    }

                    $output[] = array('type' => 'Cell Reference', 'value' => $val, 'reference' => $val);
//                    $expectingOperator = false;
                } else {    // it's a variable, constant, string, number or boolean
//                    echo 'Element is a Variable, Constant, String, Number or Boolean<br />';
                    //    If the last entry on the stack was a : operator, then we may have a row or column range reference
                    $testPrevOp = $stack->last(1);
                    if ($testPrevOp['value'] == ':') {
                        $startRowColRef = $output[count($output)-1]['value'];
                        $rangeWS1 = '';
                        if (strpos('!',$startRowColRef) !== false) {
                            list($rangeWS1,$startRowColRef) = explode('!',$startRowColRef);
                        }
                        if ($rangeWS1 != '') $rangeWS1 .= '!';
                        $rangeWS2 = $rangeWS1;
                        if (strpos('!',$val) !== false) {
                            list($rangeWS2,$val) = explode('!',$val);
                        }
                        if ($rangeWS2 != '') $rangeWS2 .= '!';
                        if ((is_integer($startRowColRef)) && (ctype_digit($val)) &&
                            ($startRowColRef <= 1048576) && ($val <= 1048576)) {
                            //    Row range
                            $endRowColRef = (!is_null($pCellParent)) ? $pCellParent->getHighestColumn() : 'XFD';    //    Max 16,384 columns for Excel2007
                            $output[count($output)-1]['value'] = $rangeWS1.'A'.$startRowColRef;
                            $val = $rangeWS2.$endRowColRef.$val;
                        } elseif ((ctype_alpha($startRowColRef)) && (ctype_alpha($val)) &&
                            (strlen($startRowColRef) <= 3) && (strlen($val) <= 3)) {
                            //    Column range
                            $endRowColRef = (!is_null($pCellParent)) ? $pCellParent->getHighestRow() : 1048576;        //    Max 1,048,576 rows for Excel2007
                            $output[count($output)-1]['value'] = $rangeWS1.strtoupper($startRowColRef).'1';
                            $val = $rangeWS2.$val.$endRowColRef;
                        }
                    }

                    $localeConstant = false;
                    if ($opCharacter == '"') {
//                        echo 'Element is a String<br />';
                        //    UnEscape any quotes within the string
                        $val = self::_wrapResult(str_replace('""','"',self::_unwrapResult($val)));
                    } elseif (is_numeric($val)) {
//                        echo 'Element is a Number<br />';
                        if ((strpos($val,'.') !== false) || (stripos($val,'e') !== false) || ($val > PHP_INT_MAX) || ($val < -PHP_INT_MAX)) {
//                            echo 'Casting '.$val.' to float<br />';
                            $val = (float) $val;
                        } else {
//                            echo 'Casting '.$val.' to integer<br />';
                            $val = (integer) $val;
                        }
                    } elseif (isset(self::$_ExcelConstants[trim(strtoupper($val))])) {
                        $excelConstant = trim(strtoupper($val));
//                        echo 'Element '.$excelConstant.' is an Excel Constant<br />';
                        $val = self::$_ExcelConstants[$excelConstant];
                    } elseif (($localeConstant = array_search(trim(strtoupper($val)), self::$_localeBoolean)) !== false) {
//                        echo 'Element '.$localeConstant.' is an Excel Constant<br />';
                        $val = self::$_ExcelConstants[$localeConstant];
                    }
                    $details = array('type' => 'Value', 'value' => $val, 'reference' => null);
                    if ($localeConstant) { $details['localeValue'] = $localeConstant; }
                    $output[] = $details;
                }
                $index += $length;

            } elseif ($opCharacter == '$') {    // absolute row or column range
                ++$index;
            } elseif ($opCharacter == ')') {    // miscellaneous error checking
                if ($expectingOperand) {
                    $output[] = array('type' => 'Null Value', 'value' => self::$_ExcelConstants['NULL'], 'reference' => null);
                    $expectingOperand = false;
                    $expectingOperator = true;
                } else {
                    return $this->_raiseFormulaError("Formula Error: Unexpected ')'");
                }
            } elseif (isset(self::$_operators[$opCharacter]) && !$expectingOperator) {
                return $this->_raiseFormulaError("Formula Error: Unexpected operator '$opCharacter'");
            } else {    // I don't even want to know what you did to get here
                return $this->_raiseFormulaError("Formula Error: An unexpected error occured");
            }
            //    Test for end of formula string
            if ($index == strlen($formula)) {
                //    Did we end with an operator?.
                //    Only valid for the % unary operator
                if ((isset(self::$_operators[$opCharacter])) && ($opCharacter != '%')) {
                    return $this->_raiseFormulaError("Formula Error: Operator '$opCharacter' has no operands");
                } else {
                    break;
                }
            }
            //    Ignore white space
            while (($formula{$index} == "\n") || ($formula{$index} == "\r")) {
                ++$index;
            }
            if ($formula{$index} == ' ') {
                while ($formula{$index} == ' ') {
                    ++$index;
                }
                //    If we're expecting an operator, but only have a space between the previous and next operands (and both are
                //        Cell References) then we have an INTERSECTION operator
//                echo 'Possible Intersect Operator<br />';
                if (($expectingOperator) && (preg_match('/^'.self::CALCULATION_REGEXP_CELLREF.'.*/Ui', substr($formula, $index), $match)) &&
                    ($output[count($output)-1]['type'] == 'Cell Reference')) {
//                    echo 'Element is an Intersect Operator<br />';
                    while($stack->count() > 0 &&
                        ($o2 = $stack->last()) &&
                        isset(self::$_operators[$o2['value']]) &&
                        @($operatorAssociativity[$opCharacter] ? $operatorPrecedence[$opCharacter] < $operatorPrecedence[$o2['value']] : $operatorPrecedence[$opCharacter] <= $operatorPrecedence[$o2['value']])) {
                        $output[] = $stack->pop();                                //    Swap operands and higher precedence operators from the stack to the output
                    }
                    $stack->push('Binary Operator','|');    //    Put an Intersect Operator on the stack
                    $expectingOperator = false;
                }
            }
        }

        while (!is_null($op = $stack->pop())) {    // pop everything off the stack and push onto output
            if ($opCharacter['value'] == '(') return $this->_raiseFormulaError("Formula Error: Expecting ')'");    // if there are any opening braces on the stack, then braces were unbalanced
            $output[] = $op;
        }
        return $output;
    }    //    function _parseFormula()


    // evaluate postfix notation
    private function _processTokenStack($tokens, $cellID = null, PHPExcel_Cell $pCell = null) {
        if ($tokens == false) return false;

        //    If we're using cell caching, then $pCell may well be flushed back to the cache (which detaches the parent worksheet),
        //        so we store the parent worksheet so that we can re-attach it when necessary
        $pCellParent = (!is_null($pCell)) ? $pCell->getParent() : null;
        $stack = new PHPExcel_Token_Stack;

        //    Loop through each token in turn
        foreach ($tokens as $tokenData) {
//            print_r($tokenData);
//            echo '<br />';
            $token = $tokenData['value'];
//            echo '<b>Token is '.$token.'</b><br />';
            // if the token is a binary operator, pop the top two values off the stack, do the operation, and push the result back on the stack
            if (isset(self::$_binaryOperators[$token])) {
//                echo 'Token is a binary operator<br />';
                //    We must have two operands, error if we don't
                if (is_null($operand2Data = $stack->pop())) return $this->_raiseFormulaError('Internal error - Operand value missing from stack');
                if (is_null($operand1Data = $stack->pop())) return $this->_raiseFormulaError('Internal error - Operand value missing from stack');
                //    Log what we're doing
                $operand1 = $operand1Data['value'];
                $operand2 = $operand2Data['value'];
                if ($token == ':') {
                    $this->_writeDebug('Evaluating Range '.$this->_showValue($operand1Data['reference']).$token.$this->_showValue($operand2Data['reference']));
                } else {
                    $this->_writeDebug('Evaluating '.$this->_showValue($operand1).' '.$token.' '.$this->_showValue($operand2));
                }
                //    Process the operation in the appropriate manner
                switch ($token) {
                    //    Comparison (Boolean) Operators
                    case '>'    :            //    Greater than
                    case '<'    :            //    Less than
                    case '>='    :            //    Greater than or Equal to
                    case '<='    :            //    Less than or Equal to
                    case '='    :            //    Equality
                    case '<>'    :            //    Inequality
                        $this->_executeBinaryComparisonOperation($cellID,$operand1,$operand2,$token,$stack);
                        break;
                    //    Binary Operators
                    case ':'    :            //    Range
                        $sheet1 = $sheet2 = '';
                        if (strpos($operand1Data['reference'],'!') !== false) {
                            list($sheet1,$operand1Data['reference']) = explode('!',$operand1Data['reference']);
                        } else {
                            $sheet1 = (!is_null($pCellParent)) ? $pCellParent->getTitle() : '';
                        }
                        if (strpos($operand2Data['reference'],'!') !== false) {
                            list($sheet2,$operand2Data['reference']) = explode('!',$operand2Data['reference']);
                        } else {
                            $sheet2 = $sheet1;
                        }
                        if ($sheet1 == $sheet2) {
                            if (is_null($operand1Data['reference'])) {
                                if ((trim($operand1Data['value']) != '') && (is_numeric($operand1Data['value']))) {
                                    $operand1Data['reference'] = $pCell->getColumn().$operand1Data['value'];
                                } elseif (trim($operand1Data['reference']) == '') {
                                    $operand1Data['reference'] = $pCell->getCoordinate();
                                } else {
                                    $operand1Data['reference'] = $operand1Data['value'].$pCell->getRow();
                                }
                            }
                            if (is_null($operand2Data['reference'])) {
                                if ((trim($operand2Data['value']) != '') && (is_numeric($operand2Data['value']))) {
                                    $operand2Data['reference'] = $pCell->getColumn().$operand2Data['value'];
                                } elseif (trim($operand2Data['reference']) == '') {
                                    $operand2Data['reference'] = $pCell->getCoordinate();
                                } else {
                                    $operand2Data['reference'] = $operand2Data['value'].$pCell->getRow();
                                }
                            }

                            $oData = array_merge(explode(':',$operand1Data['reference']),explode(':',$operand2Data['reference']));
                            $oCol = $oRow = array();
                            foreach($oData as $oDatum) {
                                $oCR = PHPExcel_Cell::coordinateFromString($oDatum);
                                $oCol[] = PHPExcel_Cell::columnIndexFromString($oCR[0]) - 1;
                                $oRow[] = $oCR[1];
                            }
                            $cellRef = PHPExcel_Cell::stringFromColumnIndex(min($oCol)).min($oRow).':'.PHPExcel_Cell::stringFromColumnIndex(max($oCol)).max($oRow);
                            if (!is_null($pCellParent)) {
                                $cellValue = $this->extractCellRange($cellRef, $pCellParent->getParent()->getSheetByName($sheet1), false);
                            } else {
                                return $this->_raiseFormulaError('Unable to access Cell Reference');
                            }
                            $stack->push('Cell Reference',$cellValue,$cellRef);
                        } else {
                            $stack->push('Error',PHPExcel_Calculation_Functions::REF(),null);
                        }

                        break;
                    case '+'    :            //    Addition
                        $this->_executeNumericBinaryOperation($cellID,$operand1,$operand2,$token,'plusEquals',$stack);
                        break;
                    case '-'    :            //    Subtraction
                        $this->_executeNumericBinaryOperation($cellID,$operand1,$operand2,$token,'minusEquals',$stack);
                        break;
                    case '*'    :            //    Multiplication
                        $this->_executeNumericBinaryOperation($cellID,$operand1,$operand2,$token,'arrayTimesEquals',$stack);
                        break;
                    case '/'    :            //    Division
                        $this->_executeNumericBinaryOperation($cellID,$operand1,$operand2,$token,'arrayRightDivide',$stack);
                        break;
                    case '^'    :            //    Exponential
                        $this->_executeNumericBinaryOperation($cellID,$operand1,$operand2,$token,'power',$stack);
                        break;
                    case '&'    :            //    Concatenation
                        //    If either of the operands is a matrix, we need to treat them both as matrices
                        //        (converting the other operand to a matrix if need be); then perform the required
                        //        matrix operation
                        if (is_bool($operand1)) {
                            $operand1 = ($operand1) ? self::$_localeBoolean['TRUE'] : self::$_localeBoolean['FALSE'];
                        }
                        if (is_bool($operand2)) {
                            $operand2 = ($operand2) ? self::$_localeBoolean['TRUE'] : self::$_localeBoolean['FALSE'];
                        }
                        if ((is_array($operand1)) || (is_array($operand2))) {
                            //    Ensure that both operands are arrays/matrices
                            self::_checkMatrixOperands($operand1,$operand2,2);
                            try {
                                //    Convert operand 1 from a PHP array to a matrix
                                $matrix = new PHPExcel_Shared_JAMA_Matrix($operand1);
                                //    Perform the required operation against the operand 1 matrix, passing in operand 2
                                $matrixResult = $matrix->concat($operand2);
                                $result = $matrixResult->getArray();
                            } catch (Exception $ex) {
                                $this->_writeDebug('JAMA Matrix Exception: '.$ex->getMessage());
                                $result = '#VALUE!';
                            }
                        } else {
                            $result = '"'.str_replace('""','"',self::_unwrapResult($operand1,'"').self::_unwrapResult($operand2,'"')).'"';
                        }
                        $this->_writeDebug('Evaluation Result is '.$this->_showTypeDetails($result));
                        $stack->push('Value',$result);
                        break;
                    case '|'    :            //    Intersect
                        $rowIntersect = array_intersect_key($operand1,$operand2);
                        $cellIntersect = $oCol = $oRow = array();
                        foreach(array_keys($rowIntersect) as $row) {
                            $oRow[] = $row;
                            foreach($rowIntersect[$row] as $col => $data) {
                                $oCol[] = PHPExcel_Cell::columnIndexFromString($col) - 1;
                                $cellIntersect[$row] = array_intersect_key($operand1[$row],$operand2[$row]);
                            }
                        }
                        $cellRef = PHPExcel_Cell::stringFromColumnIndex(min($oCol)).min($oRow).':'.PHPExcel_Cell::stringFromColumnIndex(max($oCol)).max($oRow);
                        $this->_writeDebug('Evaluation Result is '.$this->_showTypeDetails($cellIntersect));
                        $stack->push('Value',$cellIntersect,$cellRef);
                        break;
                }

            // if the token is a unary operator, pop one value off the stack, do the operation, and push it back on
            } elseif (($token === '~') || ($token === '%')) {
//                echo 'Token is a unary operator<br />';
                if (is_null($arg = $stack->pop())) return $this->_raiseFormulaError('Internal error - Operand value missing from stack');
                $arg = $arg['value'];
                if ($token === '~') {
//                    echo 'Token is a negation operator<br />';
                    $this->_writeDebug('Evaluating Negation of '.$this->_showValue($arg));
                    $multiplier = -1;
                } else {
//                    echo 'Token is a percentile operator<br />';
                    $this->_writeDebug('Evaluating Percentile of '.$this->_showValue($arg));
                    $multiplier = 0.01;
                }
                if (is_array($arg)) {
                    self::_checkMatrixOperands($arg,$multiplier,2);
                    try {
                        $matrix1 = new PHPExcel_Shared_JAMA_Matrix($arg);
                        $matrixResult = $matrix1->arrayTimesEquals($multiplier);
                        $result = $matrixResult->getArray();
                    } catch (Exception $ex) {
                        $this->_writeDebug('JAMA Matrix Exception: '.$ex->getMessage());
                        $result = '#VALUE!';
                    }
                    $this->_writeDebug('Evaluation Result is '.$this->_showTypeDetails($result));
                    $stack->push('Value',$result);
                } else {
                    $this->_executeNumericBinaryOperation($cellID,$multiplier,$arg,'*','arrayTimesEquals',$stack);
                }

            } elseif (preg_match('/^'.self::CALCULATION_REGEXP_CELLREF.'$/i', $token, $matches)) {
                $cellRef = null;
//                echo 'Element '.$token.' is a Cell reference<br />';
                if (isset($matches[8])) {
//                    echo 'Reference is a Range of cells<br />';
                    if (is_null($pCell)) {
//                        We can't access the range, so return a REF error
                        $cellValue = PHPExcel_Calculation_Functions::REF();
                    } else {
                        $cellRef = $matches[6].$matches[7].':'.$matches[9].$matches[10];
                        if ($matches[2] > '') {
                            $matches[2] = trim($matches[2],"\"'");
//                            echo '$cellRef='.$cellRef.' in worksheet '.$matches[2].'<br />';
                            $this->_writeDebug('Evaluating Cell Range '.$cellRef.' in worksheet '.$matches[2]);
                            if (!is_null($pCellParent)) {
                                $cellValue = $this->extractCellRange($cellRef, $pCellParent->getParent()->getSheetByName($matches[2]), false);
                            } else {
                                return $this->_raiseFormulaError('Unable to access Cell Reference');
                            }
                            $this->_writeDebug('Evaluation Result for cells '.$cellRef.' in worksheet '.$matches[2].' is '.$this->_showTypeDetails($cellValue));
//                            $cellRef = $matches[2].'!'.$cellRef;
                        } else {
//                            echo '$cellRef='.$cellRef.' in current worksheet<br />';
                            $this->_writeDebug('Evaluating Cell Range '.$cellRef.' in current worksheet');
                            if (!is_null($pCellParent)) {
                                $cellValue = $this->extractCellRange($cellRef, $pCellParent, false);
                            } else {
                                return $this->_raiseFormulaError('Unable to access Cell Reference');
                            }
                            $this->_writeDebug('Evaluation Result for cells '.$cellRef.' is '.$this->_showTypeDetails($cellValue));
                        }
                    }
                } else {
//                    echo 'Reference is a single Cell<br />';
                    if (is_null($pCell)) {
//                        We can't access the cell, so return a REF error
                        $cellValue = PHPExcel_Calculation_Functions::REF();
                    } else {
                        $cellRef = $matches[6].$matches[7];
                        if ($matches[2] > '') {
                            $matches[2] = trim($matches[2],"\"'");
//                            echo '$cellRef='.$cellRef.' in worksheet '.$matches[2].'<br />';
                            $this->_writeDebug('Evaluating Cell '.$cellRef.' in worksheet '.$matches[2]);
                            if (!is_null($pCellParent)) {
                                if ($pCellParent->getParent()->getSheetByName($matches[2])->cellExists($cellRef)) {
                                    $cellValue = $this->extractCellRange($cellRef, $pCellParent->getParent()->getSheetByName($matches[2]), false);
                                    $pCell->attach($pCellParent);
                                } else {
                                    $cellValue = null;
                                }
                            } else {
                                return $this->_raiseFormulaError('Unable to access Cell Reference');
                            }
                            $this->_writeDebug('Evaluation Result for cell '.$cellRef.' in worksheet '.$matches[2].' is '.$this->_showTypeDetails($cellValue));
//                            $cellRef = $matches[2].'!'.$cellRef;
                        } else {
//                            echo '$cellRef='.$cellRef.' in current worksheet<br />';
                            $this->_writeDebug('Evaluating Cell '.$cellRef.' in current worksheet');
                            if ($pCellParent->cellExists($cellRef)) {
                                $cellValue = $this->extractCellRange($cellRef, $pCellParent, false);
                                $pCell->attach($pCellParent);
                            } else {
                                $cellValue = null;
                            }
                            $this->_writeDebug('Evaluation Result for cell '.$cellRef.' is '.$this->_showTypeDetails($cellValue));
                        }
                    }
                }
                $stack->push('Value',$cellValue,$cellRef);

            // if the token is a function, pop arguments off the stack, hand them to the function, and push the result back on
            } elseif (preg_match('/^'.self::CALCULATION_REGEXP_FUNCTION.'$/i', $token, $matches)) {
//                echo 'Token is a function<br />';
                $functionName = $matches[1];
                $argCount = $stack->pop();
                $argCount = $argCount['value'];
                if ($functionName != 'MKMATRIX') {
                    $this->_writeDebug('Evaluating Function '.self::_localeFunc($functionName).'() with '.(($argCount == 0) ? 'no' : $argCount).' argument'.(($argCount == 1) ? '' : 's'));
                }
                if ((isset(self::$_PHPExcelFunctions[$functionName])) || (isset(self::$_controlFunctions[$functionName]))) {    // function
                    if (isset(self::$_PHPExcelFunctions[$functionName])) {
                        $functionCall = self::$_PHPExcelFunctions[$functionName]['functionCall'];
                        $passByReference = isset(self::$_PHPExcelFunctions[$functionName]['passByReference']);
                        $passCellReference = isset(self::$_PHPExcelFunctions[$functionName]['passCellReference']);
                    } elseif (isset(self::$_controlFunctions[$functionName])) {
                        $functionCall = self::$_controlFunctions[$functionName]['functionCall'];
                        $passByReference = isset(self::$_controlFunctions[$functionName]['passByReference']);
                        $passCellReference = isset(self::$_controlFunctions[$functionName]['passCellReference']);
                    }
                    // get the arguments for this function
//                    echo 'Function '.$functionName.' expects '.$argCount.' arguments<br />';
                    $args = $argArrayVals = array();
                    for ($i = 0; $i < $argCount; ++$i) {
                        $arg = $stack->pop();
                        $a = $argCount - $i - 1;
                        if (($passByReference) &&
                            (isset(self::$_PHPExcelFunctions[$functionName]['passByReference'][$a])) &&
                            (self::$_PHPExcelFunctions[$functionName]['passByReference'][$a])) {
                            if (is_null($arg['reference'])) {
                                $args[] = $cellID;
                                if ($functionName != 'MKMATRIX') { $argArrayVals[] = $this->_showValue($cellID); }
                            } else {
                                $args[] = $arg['reference'];
                                if ($functionName != 'MKMATRIX') { $argArrayVals[] = $this->_showValue($arg['reference']); }
                            }
                        } else {
                            $args[] = self::_unwrapResult($arg['value']);
                            if ($functionName != 'MKMATRIX') { $argArrayVals[] = $this->_showValue($arg['value']); }
                        }
                    }
                    //    Reverse the order of the arguments
                    krsort($args);
                    if (($passByReference) && ($argCount == 0)) {
                        $args[] = $cellID;
                        $argArrayVals[] = $this->_showValue($cellID);
                    }
//                    echo 'Arguments are: ';
//                    print_r($args);
//                    echo '<br />';
                    if ($functionName != 'MKMATRIX') {
                        if ($this->writeDebugLog) {
                            krsort($argArrayVals);
                            $this->_writeDebug('Evaluating '. self::_localeFunc($functionName).'( '.implode(self::$_localeArgumentSeparator.' ',PHPExcel_Calculation_Functions::flattenArray($argArrayVals)).' )');
                        }
                    }
                    //    Process each argument in turn, building the return value as an array
//                    if (($argCount == 1) && (is_array($args[1])) && ($functionName != 'MKMATRIX')) {
//                        $operand1 = $args[1];
//                        $this->_writeDebug('Argument is a matrix: '.$this->_showValue($operand1));
//                        $result = array();
//                        $row = 0;
//                        foreach($operand1 as $args) {
//                            if (is_array($args)) {
//                                foreach($args as $arg) {
//                                    $this->_writeDebug('Evaluating '.self::_localeFunc($functionName).'( '.$this->_showValue($arg).' )');
//                                    $r = call_user_func_array($functionCall,$arg);
//                                    $this->_writeDebug('Evaluation Result for '.self::_localeFunc($functionName).'() function call is '.$this->_showTypeDetails($r));
//                                    $result[$row][] = $r;
//                                }
//                                ++$row;
//                            } else {
//                                $this->_writeDebug('Evaluating '.self::_localeFunc($functionName).'( '.$this->_showValue($args).' )');
//                                $r = call_user_func_array($functionCall,$args);
//                                $this->_writeDebug('Evaluation Result for '.self::_localeFunc($functionName).'() function call is '.$this->_showTypeDetails($r));
//                                $result[] = $r;
//                            }
//                        }
//                    } else {
                    //    Process the argument with the appropriate function call
                        if ($passCellReference) {
                            $args[] = $pCell;
                        }
                        if (strpos($functionCall,'::') !== false) {
                            $result = call_user_func_array(explode('::',$functionCall),$args);
                        } else {
                            foreach($args as &$arg) {
                                $arg = PHPExcel_Calculation_Functions::flattenSingleValue($arg);
                            }
                            unset($arg);
                            $result = call_user_func_array($functionCall,$args);
                        }
//                    }
                    if ($functionName != 'MKMATRIX') {
                        $this->_writeDebug('Evaluation Result for '.self::_localeFunc($functionName).'() function call is '.$this->_showTypeDetails($result));
                    }
                    $stack->push('Value',self::_wrapResult($result));
                }

            } else {
                // if the token is a number, boolean, string or an Excel error, push it onto the stack
                if (isset(self::$_ExcelConstants[strtoupper($token)])) {
                    $excelConstant = strtoupper($token);
//                    echo 'Token is a PHPExcel constant: '.$excelConstant.'<br />';
                    $stack->push('Constant Value',self::$_ExcelConstants[$excelConstant]);
                    $this->_writeDebug('Evaluating Constant '.$excelConstant.' as '.$this->_showTypeDetails(self::$_ExcelConstants[$excelConstant]));
                } elseif ((is_numeric($token)) || (is_null($token)) || (is_bool($token)) || ($token == '') || ($token{0} == '"') || ($token{0} == '#')) {
//                    echo 'Token is a number, boolean, string, null or an Excel error<br />';
                    $stack->push('Value',$token);
                // if the token is a named range, push the named range name onto the stack
                } elseif (preg_match('/^'.self::CALCULATION_REGEXP_NAMEDRANGE.'$/i', $token, $matches)) {
//                    echo 'Token is a named range<br />';
                    $namedRange = $matches[6];
//                    echo 'Named Range is '.$namedRange.'<br />';
                    $this->_writeDebug('Evaluating Named Range '.$namedRange);
                    $cellValue = $this->extractNamedRange($namedRange, ((null !== $pCell) ? $pCellParent : null), false);
                    $pCell->attach($pCellParent);
                    $this->_writeDebug('Evaluation Result for named range '.$namedRange.' is '.$this->_showTypeDetails($cellValue));
                    $stack->push('Named Range',$cellValue,$namedRange);
                } else {
                    return $this->_raiseFormulaError("undefined variable '$token'");
                }
            }
        }
        // when we're out of tokens, the stack should have a single element, the final result
        if ($stack->count() != 1) return $this->_raiseFormulaError("internal error");
        $output = $stack->pop();
        $output = $output['value'];

//        if ((is_array($output)) && (self::$returnArrayAsType != self::RETURN_ARRAY_AS_ARRAY)) {
//            return array_shift(PHPExcel_Calculation_Functions::flattenArray($output));
//        }
        return $output;
    }    //    function _processTokenStack()


    private function _validateBinaryOperand($cellID,&$operand,&$stack) {
        //    Numbers, matrices and booleans can pass straight through, as they're already valid
        if (is_string($operand)) {
            //    We only need special validations for the operand if it is a string
            //    Start by stripping off the quotation marks we use to identify true excel string values internally
            if ($operand > '' && $operand{0} == '"') { $operand = self::_unwrapResult($operand); }
            //    If the string is a numeric value, we treat it as a numeric, so no further testing
            if (!is_numeric($operand)) {
                //    If not a numeric, test to see if the value is an Excel error, and so can't be used in normal binary operations
                if ($operand > '' && $operand{0} == '#') {
                    $stack->push('Value', $operand);
                    $this->_writeDebug('Evaluation Result is '.$this->_showTypeDetails($operand));
                    return false;
                } elseif (!PHPExcel_Shared_String::convertToNumberIfFraction($operand)) {
                    //    If not a numeric or a fraction, then it's a text string, and so can't be used in mathematical binary operations
                    $stack->push('Value', '#VALUE!');
                    $this->_writeDebug('Evaluation Result is a '.$this->_showTypeDetails('#VALUE!'));
                    return false;
                }
            }
        }

        //    return a true if the value of the operand is one that we can use in normal binary operations
        return true;
    }    //    function _validateBinaryOperand()


    private function _executeBinaryComparisonOperation($cellID,$operand1,$operand2,$operation,&$stack,$recursingArrays=false) {
        //    If we're dealing with matrix operations, we want a matrix result
        if ((is_array($operand1)) || (is_array($operand2))) {
            $result = array();
            if ((is_array($operand1)) && (!is_array($operand2))) {
                foreach($operand1 as $x => $operandData) {
                    $this->_writeDebug('Evaluating '.$this->_showValue($operandData).' '.$operation.' '.$this->_showValue($operand2));
                    $this->_executeBinaryComparisonOperation($cellID,$operandData,$operand2,$operation,$stack);
                    $r = $stack->pop();
                    $result[$x] = $r['value'];
                }
            } elseif ((!is_array($operand1)) && (is_array($operand2))) {
                foreach($operand2 as $x => $operandData) {
                    $this->_writeDebug('Evaluating '.$this->_showValue($operand1).' '.$operation.' '.$this->_showValue($operandData));
                    $this->_executeBinaryComparisonOperation($cellID,$operand1,$operandData,$operation,$stack);
                    $r = $stack->pop();
                    $result[$x] = $r['value'];
                }
            } else {
                if (!$recursingArrays) { self::_checkMatrixOperands($operand1,$operand2,2); }
                foreach($operand1 as $x => $operandData) {
                    $this->_writeDebug('Evaluating '.$this->_showValue($operandData).' '.$operation.' '.$this->_showValue($operand2[$x]));
                    $this->_executeBinaryComparisonOperation($cellID,$operandData,$operand2[$x],$operation,$stack,true);
                    $r = $stack->pop();
                    $result[$x] = $r['value'];
                }
            }
            //    Log the result details
            $this->_writeDebug('Evaluation Result is '.$this->_showTypeDetails($result));
            //    And push the result onto the stack
            $stack->push('Array',$result);
            return true;
        }

        //    Simple validate the two operands if they are string values
        if (is_string($operand1) && $operand1 > '' && $operand1{0} == '"') { $operand1 = self::_unwrapResult($operand1); }
        if (is_string($operand2) && $operand2 > '' && $operand2{0} == '"') { $operand2 = self::_unwrapResult($operand2); }

        //    execute the necessary operation
        switch ($operation) {
            //    Greater than
            case '>':
                $result = ($operand1 > $operand2);
                break;
            //    Less than
            case '<':
                $result = ($operand1 < $operand2);
                break;
            //    Equality
            case '=':
                $result = ($operand1 == $operand2);
                break;
            //    Greater than or equal
            case '>=':
                $result = ($operand1 >= $operand2);
                break;
            //    Less than or equal
            case '<=':
                $result = ($operand1 <= $operand2);
                break;
            //    Inequality
            case '<>':
                $result = ($operand1 != $operand2);
                break;
        }

        //    Log the result details
        $this->_writeDebug('Evaluation Result is '.$this->_showTypeDetails($result));
        //    And push the result onto the stack
        $stack->push('Value',$result);
        return true;
    }    //    function _executeBinaryComparisonOperation()


    private function _executeNumericBinaryOperation($cellID,$operand1,$operand2,$operation,$matrixFunction,&$stack) {
        //    Validate the two operands
        if (!$this->_validateBinaryOperand($cellID,$operand1,$stack)) return false;
        if (!$this->_validateBinaryOperand($cellID,$operand2,$stack)) return false;

        $executeMatrixOperation = false;
        //    If either of the operands is a matrix, we need to treat them both as matrices
        //        (converting the other operand to a matrix if need be); then perform the required
        //        matrix operation
        if ((is_array($operand1)) || (is_array($operand2))) {
            //    Ensure that both operands are arrays/matrices
            $executeMatrixOperation = true;
            $mSize = array();
            list($mSize[],$mSize[],$mSize[],$mSize[]) = self::_checkMatrixOperands($operand1,$operand2,2);

            //    But if they're both single cell matrices, then we can treat them as simple values
            if (array_sum($mSize) == 4) {
                $executeMatrixOperation = false;
                $operand1 = $operand1[0][0];
                $operand2 = $operand2[0][0];
            }
        }

        if ($executeMatrixOperation) {
            try {
                //    Convert operand 1 from a PHP array to a matrix
                $matrix = new PHPExcel_Shared_JAMA_Matrix($operand1);
                //    Perform the required operation against the operand 1 matrix, passing in operand 2
                $matrixResult = $matrix->$matrixFunction($operand2);
                $result = $matrixResult->getArray();
            } catch (Exception $ex) {
                $this->_writeDebug('JAMA Matrix Exception: '.$ex->getMessage());
                $result = '#VALUE!';
            }
        } else {
            if ((PHPExcel_Calculation_Functions::getCompatibilityMode() != PHPExcel_Calculation_Functions::COMPATIBILITY_OPENOFFICE) &&
                ((is_string($operand1) && !is_numeric($operand1)) || (is_string($operand2) && !is_numeric($operand2)))) {
                $result = PHPExcel_Calculation_Functions::VALUE();
            } else {
                //    If we're dealing with non-matrix operations, execute the necessary operation
                switch ($operation) {
                    //    Addition
                    case '+':
                        $result = $operand1+$operand2;
                        break;
                    //    Subtraction
                    case '-':
                        $result = $operand1-$operand2;
                        break;
                    //    Multiplication
                    case '*':
                        $result = $operand1*$operand2;
                        break;
                    //    Division
                    case '/':
                        if ($operand2 == 0) {
                            //    Trap for Divide by Zero error
                            $stack->push('Value','#DIV/0!');
                            $this->_writeDebug('Evaluation Result is '.$this->_showTypeDetails('#DIV/0!'));
                            return false;
                        } else {
                            $result = $operand1/$operand2;
                        }
                        break;
                    //    Power
                    case '^':
                        $result = pow($operand1,$operand2);
                        break;
                }
            }
        }

        //    Log the result details
        $this->_writeDebug('Evaluation Result is '.$this->_showTypeDetails($result));
        //    And push the result onto the stack
        $stack->push('Value',$result);
        return true;
    }    //    function _executeNumericBinaryOperation()


    private function _writeDebug($message) {
        //    Only write the debug log if logging is enabled
        if ($this->writeDebugLog) {
            if ($this->echoDebugLog) {
                echo implode(' -> ',$this->debugLogStack).' -> '.$message,'<br />';
            }
            $this->debugLog[] = implode(' -> ',$this->debugLogStack).' -> '.$message;
        }
    }    //    function _writeDebug()


    // trigger an error, but nicely, if need be
    protected function _raiseFormulaError($errorMessage) {
        $this->formulaError = $errorMessage;
        if (!$this->suppressFormulaErrors) throw new Exception($errorMessage);
        trigger_error($errorMessage, E_USER_ERROR);
    }    //    function _raiseFormulaError()


    /**
     * Extract range values
     *
     * @param    string                &$pRange        String based range representation
     * @param    PHPExcel_Worksheet    $pSheet        Worksheet
     * @return  mixed                Array of values in range if range contains more than one element. Otherwise, a single value is returned.
     * @throws    Exception
     */
    public function extractCellRange(&$pRange = 'A1', PHPExcel_Worksheet $pSheet = null, $resetLog=true) {
        // Return value
        $returnValue = array ();

//        echo 'extractCellRange('.$pRange.')<br />';
        if (!is_null($pSheet)) {
//            echo 'Passed sheet name is '.$pSheet->getTitle().'<br />';
//            echo 'Range reference is '.$pRange.'<br />';
            if (strpos ($pRange, '!') !== false) {
//                echo '$pRange reference includes sheet reference<br />';
                $worksheetReference = PHPExcel_Worksheet::extractSheetTitle($pRange, true);
                $pSheet = $pSheet->getParent()->getSheetByName($worksheetReference[0]);
//                echo 'New sheet name is '.$pSheet->getTitle().'<br />';
                $pRange = $worksheetReference[1];
//                echo 'Adjusted Range reference is '.$pRange.'<br />';
            }

            // Extract range
            $aReferences = PHPExcel_Cell::extractAllCellReferencesInRange($pRange);
            $pRange = $pSheet->getTitle().'!'.$pRange;
            if (!isset($aReferences[1])) {
                //    Single cell in range
                list($currentCol,$currentRow) = sscanf($aReferences[0],'%[A-Z]%d');
                if ($pSheet->cellExists($aReferences[0])) {
                    $returnValue[$currentRow][$currentCol] = $pSheet->getCell($aReferences[0])->getCalculatedValue($resetLog);
                } else {
                    $returnValue[$currentRow][$currentCol] = null;
                }
            } else {
                // Extract cell data for all cells in the range
                foreach ($aReferences as $reference) {
                    // Extract range
                    list($currentCol,$currentRow) = sscanf($reference,'%[A-Z]%d');

                    if ($pSheet->cellExists($reference)) {
                        $returnValue[$currentRow][$currentCol] = $pSheet->getCell($reference)->getCalculatedValue($resetLog);
                    } else {
                        $returnValue[$currentRow][$currentCol] = null;
                    }
                }
            }
        }

        // Return
        return $returnValue;
    }    //    function extractCellRange()


    /**
     * Extract range values
     *
     * @param    string                &$pRange    String based range representation
     * @param    PHPExcel_Worksheet    $pSheet        Worksheet
     * @return  mixed                Array of values in range if range contains more than one element. Otherwise, a single value is returned.
     * @throws    Exception
     */
    public function extractNamedRange(&$pRange = 'A1', PHPExcel_Worksheet $pSheet = null, $resetLog=true) {
        // Return value
        $returnValue = array ();

//        echo 'extractNamedRange('.$pRange.')<br />';
        if (!is_null($pSheet)) {
//            echo 'Current sheet name is '.$pSheet->getTitle().'<br />';
//            echo 'Range reference is '.$pRange.'<br />';
            if (strpos ($pRange, '!') !== false) {
//                echo '$pRange reference includes sheet reference<br />';
                $worksheetReference = PHPExcel_Worksheet::extractSheetTitle($pRange, true);
                $pSheet = $pSheet->getParent()->getSheetByName($worksheetReference[0]);
//                echo 'New sheet name is '.$pSheet->getTitle().'<br />';
                $pRange = $worksheetReference[1];
//                echo 'Adjusted Range reference is '.$pRange.'<br />';
            }

            // Named range?
            $namedRange = PHPExcel_NamedRange::resolveRange($pRange, $pSheet);
            if (!is_null($namedRange)) {
                $pSheet = $namedRange->getWorksheet();
//                echo 'Named Range '.$pRange.' (';
                $pRange = $namedRange->getRange();
                $splitRange = PHPExcel_Cell::splitRange($pRange);
                //    Convert row and column references
                if (ctype_alpha($splitRange[0][0])) {
                    $pRange = $splitRange[0][0] . '1:' . $splitRange[0][1] . $namedRange->getWorksheet()->getHighestRow();
                } elseif(ctype_digit($splitRange[0][0])) {
                    $pRange = 'A' . $splitRange[0][0] . ':' . $namedRange->getWorksheet()->getHighestColumn() . $splitRange[0][1];
                }
//                echo $pRange.') is in sheet '.$namedRange->getWorksheet()->getTitle().'<br />';

//                if ($pSheet->getTitle() != $namedRange->getWorksheet()->getTitle()) {
//                    if (!$namedRange->getLocalOnly()) {
//                        $pSheet = $namedRange->getWorksheet();
//                    } else {
//                        return $returnValue;
//                    }
//                }
            } else {
                return PHPExcel_Calculation_Functions::REF();
            }

            // Extract range
            $aReferences = PHPExcel_Cell::extractAllCellReferencesInRange($pRange);
//            var_dump($aReferences);
            if (!isset($aReferences[1])) {
                //    Single cell (or single column or row) in range
                list($currentCol,$currentRow) = PHPExcel_Cell::coordinateFromString($aReferences[0]);
                if ($pSheet->cellExists($aReferences[0])) {
                    $returnValue[$currentRow][$currentCol] = $pSheet->getCell($aReferences[0])->getCalculatedValue($resetLog);
                } else {
                    $returnValue[$currentRow][$currentCol] = null;
                }
            } else {
                // Extract cell data for all cells in the range
                foreach ($aReferences as $reference) {
                    // Extract range
                    list($currentCol,$currentRow) = PHPExcel_Cell::coordinateFromString($reference);
//                    echo 'NAMED RANGE: $currentCol='.$currentCol.' $currentRow='.$currentRow.'<br />';
                    if ($pSheet->cellExists($reference)) {
                        $returnValue[$currentRow][$currentCol] = $pSheet->getCell($reference)->getCalculatedValue($resetLog);
                    } else {
                        $returnValue[$currentRow][$currentCol] = null;
                    }
                }
            }
//                print_r($returnValue);
//            echo '<br />';
        }

        // Return
        return $returnValue;
    }    //    function extractNamedRange()


    /**
     * Is a specific function implemented?
     *
     * @param    string    $pFunction    Function Name
     * @return    boolean
     */
    public function isImplemented($pFunction = '') {
        $pFunction = strtoupper ($pFunction);
        if (isset(self::$_PHPExcelFunctions[$pFunction])) {
            return (self::$_PHPExcelFunctions[$pFunction]['functionCall'] != 'PHPExcel_Calculation_Functions::DUMMY');
        } else {
            return false;
        }
    }    //    function isImplemented()


    /**
     * Get a list of all implemented functions as an array of function objects
     *
     * @return    array of PHPExcel_Calculation_Function
     */
    public function listFunctions() {
        // Return value
        $returnValue = array();
        // Loop functions
        foreach(self::$_PHPExcelFunctions as $functionName => $function) {
            if ($function['functionCall'] != 'PHPExcel_Calculation_Functions::DUMMY') {
                $returnValue[$functionName] = new PHPExcel_Calculation_Function($function['category'],
                                                                                $functionName,
                                                                                $function['functionCall']
                                                                               );
            }
        }

        // Return
        return $returnValue;
    }    //    function listFunctions()


    /**
     * Get a list of all Excel function names
     *
     * @return    array
     */
    public function listAllFunctionNames() {
        return array_keys(self::$_PHPExcelFunctions);
    }    //    function listAllFunctionNames()

    /**
     * Get a list of implemented Excel function names
     *
     * @return    array
     */
    public function listFunctionNames() {
        // Return value
        $returnValue = array();
        // Loop functions
        foreach(self::$_PHPExcelFunctions as $functionName => $function) {
            if ($function['functionCall'] != 'PHPExcel_Calculation_Functions::DUMMY') {
                $returnValue[] = $functionName;
            }
        }

        // Return
        return $returnValue;
    }    //    function listFunctionNames()

}    //    class PHPExcel_Calculation




// for internal use
class PHPExcel_Token_Stack {

    private $_stack = array();
    private $_count = 0;


    public function count() {
        return $this->_count;
    }    //    function count()


    public function push($type,$value,$reference=null) {
        $this->_stack[$this->_count++] = array('type'        => $type,
                                               'value'        => $value,
                                               'reference'    => $reference
                                              );
        if ($type == 'Function') {
            $localeFunction = PHPExcel_Calculation::_localeFunc($value);
            if ($localeFunction != $value) {
                $this->_stack[($this->_count - 1)]['localeValue'] = $localeFunction;
            }
        }
    }    //    function push()


    public function pop() {
        if ($this->_count > 0) {
            return $this->_stack[--$this->_count];
        }
        return null;
    }    //    function pop()


    public function last($n=1) {
        if ($this->_count-$n < 0) {
            return null;
        }
        return $this->_stack[$this->_count-$n];
    }    //    function last()


    function __construct() {
    }

}    //    class PHPExcel_Token_Stack
